I'm new to the writing world (other than writing a lot as a child). I want to write my story to help empower women in similar situations but it involves writing about my ex. How does one tell their story that involves others and can place them in a bad light? If it's all truth, am I okay to write it? Or do I need to change the names?
Is your goal to publicly shame your ex-husband, or to provide advice and warning to other women?
You seem to indicate (b). In that case, I'd advise you to avoid naming names. Write a fiction story with a character who does the bad things your husband did, but give him a different name and make him different in other ways. Like if your ex was a short, bald white coal miner, make your character a tall, long-haired black office worker. If the only thing your ex has in common with the character is the abusive behavior, than for him to sue he would have to admit to the abusive behavior. He'd have to say, "This character is obviously modeled after me, because he's a drunkard who beats up his wife and patronizes prostitutes, just like me!" He's unlikely to want to do that, and even if he did, he'd be in the position of having to say that the character is just like him in doing all these bad things, and then that you are libeling him by saying he did all these bad things.
Or write a non-fiction book where you are vague about individuals. Say "this has happened to some women". Or "this happened to a woman I know" -- presumably you know yourself very well. Maybe even "this happened to me" but without being specific about who the perpetrator was. If you've only had one husband, don't say "an ex-husband", just say "a man with whom I had a relationship" or some such. The tail end of my previous paragraph applies just as well here.
If (a), then there's no way to accomplish this without naming him or making it obvious who you're talking about. If you publicly accuse him of doing terrible things, he has grounds for a law suit. I am not a lawyer, but my understanding of libel law is this: He'd have to prove in court that, (a) you're talking about him, and (b) your claims are false, and (c) your claims cause him harm. If you accuse him of breaking the law, that's "libel per se". He automatically passes condition (c). If you accuse him of something scandalous but that isn't illegal, than he has to prove that it caused him some harm. (Like if I wrote, "My neighbor Bob wears blue shirts", he'd have a hard time suing me for that, even if it isn't true, because it's difficult to see how he would be hurt by people thinking he wears blue shirts. Of course many real cases can be much more borderline and debatable.)
Even if you are absolutely in the right, you will likely have to hire a lawyer to defend yourself, and that will cost money. And let's be realistic: Even if you are absolutely in the right, that's no guarantee that you will win in court. One doesn't have to be a hardened cynic to say that sometimes our courts make wrong decisions.
If you want to pursue naming names, I'd second other posters here who say you should probably talk to a lawyer. A lawyer could, hopefully, give you a realistic idea of your chances of being sued and your chances of winning if you were, and an idea of what it would cost to defend yourself and the consequences of losing. People have lost tens of thousands, even millions of dollars in law suits. An exploratory session with a lawyer typically costs somewhere from nothing to one or two hundred dollars. I think that's a good investment when everything you own is at stake.
Perhaps you've gotten the clue that I'd advise not naming names unless you really, really want to hurt your ex-husband and don't care about the consequences.
We are not lawyers here, and I am not a lawyer, and you are asking for legal advice to avoid a defamation lawsuit (if it is published it is called Libel, if it is spoken it is called Slander).
The question is not whether it is true, the question will be whether you can prove it is true in a court of law, to a jury. Often you cannot; if he struck you or raped you and you have no police or medical report, if he insulted you and you have no recordings. Your word that these things are true don't count just because the court cannot tell if you are lying or not. Being willing to take a lie detector test doesn't help, those are not admitted as evidence (in the USA) because it has been proven they can be faked.
If your ex is the vindictive type, and finds out you are making money from your writing about him, he may sue you for damages and win all your money plus more. Thus victimizing you again.
Don't rely on the advice of us randos on the Internet when it comes to real liability for big money, find real sites with real lawyers or publishers talking about defenses against defamation in your work.
I'd suggest GETTING a real lawyer to advise you before you make your work public by self-publishing or actually publishing. You can finish it before then, even look for an agent or publisher to advise you. But don't expose yourself to bankruptcy by just thinking it will all be fine.
An Alternative Route.
You can publish a book of advice on how to react or deal with various kinds of threats or actions, without making it personal. i.e. "Here is a threat. Here is a way to deal with it." Leave out the part about "this happened to me, by my ex."
That might not be as cathartic for you personally, but you can write, convincingly, of the emotions one will experience and the lessons learned without putting it into the first person. Then it makes no difference if your ex says "I never did that, she's ruining my career by writing that". Because you never said he did, by name or by reference as your ex, in fact you never said anybody did that to you. You are just telling women "IF this happens to you, you are not alone, and here is one potential way to get through it."
ADDED: Some research. Here is a link to Findlaw, Elements of Libel and Slander.
Here is an excerpt from that page:
First, the plaintiff [your ex] must prove that the defendant [you] made a false and defamatory statement concerning the plaintiff.
If you published, note that "the plaintiff must prove" means they must prove this in court, (they don't have to prove it just to get you into court, they just assert this in their lawsuit) and the standard of proof will be whatever the jury decides; THEY will decide if you lied or defamed him. They might decide that if you have no proof of your claims.
Courts have long struggled with the task of determining a standard for deciding whether a statement is defamatory. Many statements may be viewed as defamatory by some individuals, but the same statement may not be viewed as defamatory by others. But generally, courts require a plaintiff to prove that he or she has been defamed in the eyes of the community or within a defined group within the community. Juries usually decide this question.
Courts have struggled to some degree with the treatment of statements of opinions. In common law, statements of opinion could form the basis of a defamation action similar to a statement of pure fact. Generally, if a statement implies defamatory facts as the basis of the opinion, then the statement may be considered libel or slander.
In a defamation action, the recipient of a communication must understand that the defendant intended to refer to the plaintiff in the communication. Even where the recipient mistakenly believes that a communication refers to the plaintiff, this belief, so long as it is reasonable, is sufficient. It is not necessary that the communication refer to the plaintiff by name. A defendant may publish defamatory material in the form of a story or novel that apparently refers only to fictitious characters, where a reasonable person would understand that a particular character actually refers to the plaintiff. This is true even if the author states that he or she intends for the work to be fictional.
It depends. If you're writing something directly autobiographical, you have practically no choice but to make direct allusions to this ex of yours. However, if you're writing a work of fiction with themes pertaining to your life, you can instead use your ex to draw a lot of inspiration, while maintaining a distinction that allows for both creative interpretation of his character and a nice slip away from defamation lawsuits.
I have several characters I base on people I know, but one character who I've drawn largely negative themes on borrows heavily from my mother, who was neglectful and resented my existence. However, I've made the character (Marissa Gemfire) considerably different from her, instead focusing on the one major theme that I derived from my relationship with her: Neglect.
As such, Marissa Gemfire ignores the protagonist, her youngest daughter, not because she's unfeeling and possibly incapable of love, but because she's simply too hedonistic; she'd much rather sleep with lots of men (my mother was never promiscuous, nor do I consider promiscuity inherently evil, rather, it's her hedonism at the expense of raising a child that's the problem); she makes time for her wants while ignoring her children.
While she does share some traits with my mother, it's largely in her effects on the protagonist; that is, she makes the protagonist feel like a mistake, making her consider her existence resented against by her own mother, meaning she has suicidal ideation from feeling like a burden, etc. Her core personal traits, being care-free, hedonistic, frankly idiotic in her callousness, they're all quite different from my mother. The only core trait I'd say she has shared with my mother is that she's more concerned with appearing to be a good mother than actually being one.
But by and large, they couldn't be more different, yet they explore themes akin to the poor relationship me and my mother had. I always feel like crap just saying 'here's what I did, try that', but honestly, I'd recommend this. Identify the theme, boil down and purify that, then construct a fictional character around that, which shares some of your ex's traits but not all.
You don't necessarily have to write about your ex. Just leave it as a husband who is an ex and whatever detail you would like to add to the character. You don't necessarily have to add your won story, though it makes whatever you are writing better.Just leave it as "This is man who is an ex." case closed.