Is there any book like this, not necessary the details I gave examples too more so the feeling.

I'll go straight to the point.
The main character is an "unreliable character" that people see as "crazy"/"too emotional" because shes either on meds or has a mental illness or is a antihero people in the book straight out dont trust her/him.
She tries to tell people, just an example, she's being stalked. No one beleives her even tho she for example sees her stalker threw the window.
Shes a good person or at least tries to be. BUT then theres THAT MOMENT (if there's a name for that I would love to know)!!! She finally "loses it" and starts doing crazy, ACTUAL CRAZY stuff to catch her stalker.
It's not exactly a climax, for example when she has to per say kill her stalker, its more of a "she gives in to the crazy side of her ", she's fed up and tries to prove herself and ussually does. Is there any book like this? Thank you:)