Your problem appears to be twofold. By writing in this way you are projecting onto this character:
- Your personality, and
- Your background
Your character is limited by the decisions YOU would make in the same situation and your story is limited by all YOUR grievances and regrets and "what ifs". Both of these issues can be solved at once: get better at writing characters.
Some people never get bored of writing characters similar or the same as themselves. But it's a good exercise to try. So take a look at yourself and put yourself into a few words. Then, get the antonyms of those words: this is your new character. If you use your head, they use their gut. If you dream of a house and family, they dream of solitude and travel. If you had siblings, they had none. And so on.
All of your characters will probably have some semblance to you, whether it's your love of peanut butter or your childhood trauma. And that's OK, but better in small doses. If you struggle with this, start with a character template. I use enneagram or Myers-Brigg to come up a basic personality type. Then when my character comes up against decisions or dilemmas, big or small, instead of looking inside my head for solutions, I instead think of that character's "type" and what they would do. Ask yourself what drives them, what are their hopes and fears, their moral values, what makes them tick.
While coming up with the personality, think about the character's history as well. What made them like this? What was their childhood like? What did they struggle with because of their hotheadedness, their absentmindedness, their being an only child? How does this effect what they hope and fear from the future?
It's likely that these answers will be different to yours. If it's important that this character is not too similar to you (as in this case), make sure they are. Remember: your character is not you. The life they have lived is different to yours. The way they choose to relive that life is different again. But only you can make them. So start at character creation and make them different!