I think, that it could be of use, to see her as two personas in one body. (She may be or maybe not actually schizophrenic, she may be just more complicated person, than she looks at first glance - more about it later, now just for simplicity let me use two personas scheme for a moment.)
First persona, which anybody can see, is a "Blonde" (cause I am blonde/ I don't have to think/ I talk like a baby/ and never pay for drink ...) - naive, cheerfull, with "superpowers" of "Empathy", "Mirror" and "Living just Here and Now" with pure heart and empty head.
She meet a boy A and from first look she LOVES him. Like TOTALLY. From deep of her heart. She believe it, she acts on it. He is just the "more FUN boy" she ever met. She is everything A ever wanted, she knows him better that his own mom and fullfill all his wishes just to make him happy (well with some acting, she would not end in bed with him this night, but makes him trust, she would really like and that it is not too far away, anyway making herself just a 'little' hard to obtain makes her just more prized in his eyes and make any progress he made much more satisfying for him.. ) ... Does not take long, they go to pub and meet A's friends, where there is one older, more serious (with better job too), say B.
She is just STUNNED how B is WISE and so she loves him from first evening they met. She loves hit like TOTALLY, from deep of her heart. Yes, A is still her old friend and she likes the fun around him and such, but it is just old friend (while kiss here or smile there does not mean nothing between old friends, you know) and it is clear, that he feels the same way (why would not he, it is soo long ago, whet it was serious between them - well at least weeks, or days or hours - he surely understand, that it is long dead history now)
She is everything B ever wanted, she uderstand him better that his own mom and fullfill all his wishes just to make him happy ... (as in previous paragraph), until one day she attend bussiness weekend with his colegues and his boss C (and guesss, what happens at that moment) ...
The other persona is a "MasterMind", who have "superpowers" like "create long time plans", "knows WhoIsWho", "Secretly Smart" and "Convice Blonde to trust anything she says". While Blonde is managing all about body, MasterMind thinks about carreer, fame, power ... not necessary evil, just a little selfish, narcistic and lazy - and have "broken moral compass".
MasterMind had long ago discovered, that showing how is she smart and responsible just leeds to lot of work and hard scolding and long morall lessons, when she does something "not so good" or just slack on something - while using Blonde style as frontend - known for being "irresponsible dumbhead all the time" brings a lot less of work and also easier one and doing anything bad just bring "oh no, again ..." response, which is much less trouble for her. So MasterMind worked hard on making better Blonde.
Yes, MasterMind had seen, how Blondes everytime jumps to a situation, steels someone hard work, ruin everything and went out mainly unharmed, confused what happened and with some unfair profit. And also had seen, how Bloneds later fall hard for just being stupid, too greedy or just too old for being the right Blonde.
But MasterMind think, that with some better planning and thinking (which those empty-head Blondes was not able to do) it would be simple and efficient way for everything - fame, power, money, jewels ... just name it. And that she just deserve it, becase she is exceptional and granted to have it all.
So well working Blonde with her excelent mind == profit!!!
MasterMind just looks at TV, hear the news, gossips and such and it is easy for her to realise, that Richard the Rich have friend D, who have friend C, who is boss of B who drinks with A who is in simple reach of Blonde.
So at right time she whisper to Blonde "the A is such FUN, would not he just be perfect friend for you?" And Blonde loses head for A. Later Mastermind whispers "A is just fun, but see, how the B is WISE, is not B who you really want?" and it happens ...
Actually the heroine is probably just the MasterMind, and the "I am Blonde" trick just was played too long and too good, that it became her second nature and mainly overtake the body from her - not that she cares, as "being Blonde" is just routine as is eating, doing homework, or simple tedious work, washing, sleeping, breathing - something she do nearly uncociously and what goes on autopilot, while she is dreaming about big future and perfect con-plans. But the habit is so perfected, that it became her personality more, than she think or is able to see.
So why there is always problem biting her back when the big success is at reach? Well, the Blonde now manage Epathy and Mirror and the Blonde believe ewrything what she wish, so her reports to MasterMind are sometime precise (as what A wants from her, when they meet first time, what are his aspirations, dreams ...), sometimes just little off or biased ("A surely thinks just of me and he loves me from his whole heart too, he would probably forgive me anything") and sometimes just pure lies (without intent, but Blonde use Empathy and Mirror against MasterMind too - she cannot NOT switch it off - so MasterMind hears just what SHE wants to hear, if there is not evidence against it)("A is my old friend and understand, that our phase of love if just deep history. He is still friend and would help me anyway, I can feel it, just trust my Empathy" - yes, it fits MasterMinds plans perfectly, so the small details - like that Blonde had not seen A from yesterday, when she met B and walked with him out, so A is probably now unsure, what happened, and thinks, that Blonde is still over head in love with him and yesterday was just bad dream, or will explain somehow naturally, like, that B is Blondes uncle - just does not came to Mastermind, after all Blonde's Empathy is real thing, we know it.)
And when next week Blonde runs to A, kiss him with "Oh hi, glad to see you, you you well, I am in hurry now" and leaves him totally confused while catching C's car, get flowers from him, kiss him and drive with him away (C:" Who was that young man", Blonde: "Ah, just some old friend of mine, it is long time ago history, but tell me ...") A:"WTF has happened, she dates B's boss now? @$%@#$%!! *)"
*) Untranslateble gealic cursing from Asterix
And Blonde still believe (as she want to believe it and there is no direct evedence against it), that A is "just old friend, who loves here a little, even after such long time not seen". While A is all to eager to get revenge, rather than to get explanation now.
MisterMind still trust Blonde anyway - she would not lie to her, as they are just one flesh and body.
Blonde is finally Rick's the Rich LOVE FOR LIFE, alone with his keys in his mansion. Mastermind whispers "what would hurt just to opent the tresor and try that diamond necklage, it must be beutifull on us and Rick surely would not mind anyway" and Blonde think so and does so, but then there are some steps on stairs - must be Rick's right hand Man, who do not trust Blonde at all. "It is too late to cover everything, so make it look like roberry, just throw some papers aroud, get the jewel box and run over balcony - I see A's car there on street, hes old friend, he will help us to gety away with it and would not ask why"
Then inevitable came, perfect plan fails. And who could expect, that A is such low man, taht not even helped Blonde, but helped her enemies and told them everything he had seen and even more. He sooo much disapointed her and after pretendind for soo long time to be friend, or even love, then he pushed her down, who knows why? (Reader know, that it is just the next time A see Blonde ater the kiss described above, climbing in negligee from Ricks the Rich Masonry, followed by some uniforms screaming "Burglar, burglar!")
- MasterMind still believes Blonde and vice versa.
- it was just all the work of the sneaky A, that perfect plan failed, nobody else is to blame
- also it was A's devil plan, that B, D, ... Rick now hates Blonde, why is A is so evil?
- Knight on white horse saved the day after all, as expected from old friend after all, he did it so many times, that one would think, he loves me or what, if he would not be just old friend of mine, who does it everytime. I would even kiss him, but he again start with his long boring moralisations, that I did not get attention to even hear
- but now we know old good friend C, who single did not turn back on us, so we can came with much better plan, and he have sooo coool car and good taste in flowers ...
and some calculation to the end:
- 99% of time everything went around the plan - MasterMind nearly won (if that A would not betray us who know why), just last 1 % time she was miscalculating
- 98% of time Blonde had fun and a lot of friends, just 2% to perfection - 1% as per As betray in the end, 1% per Knight long moralisation, but he is still our friend after all
yes, depending on which angle of view you take, the heroine was just only 1%-2% of time in trouble at all :)
(Well readers may think something else, but who they are? Can any character in the book eve see their faces?)
(Also apologies, english is non my native, second nor third lang ... lot of typos and such)