My girlfriend cheated and I am having a hard time dealing with the breakup

Hello everyone. im 22M and my ex is 21F i broke up with my girlfriend a few days ago, we was together for 5 years . she had cheated on me with a guy from work , lied to me about it and continued to lie when i had proof. she finally admitted it and things and was very affectionate and kind to me for about 3 days. it went downhill again after that and she had told me i “ deserved it” because i apparently talk to her in a horrible way when i was just trying to get my point across how i felt about the situation and telling me to “ leave” then treat her the way i am and that me being unhappy is going to cause more issues in the relationship. i dont know why i chose to stay, she is unpredictable and i feel i have to keep her close so she doesnt do anything against me. she can be very manipulative and play victim very well. she lied and said the guy from work had choked her and got him fired, when i found out about everything she suddenly went into defensive mode and told me to fuck myself because i chose sides with someone who physically abused her , none of it was true . she also told him i assulted her and that is why she doesnt trust anyone. when i found this out it really made me question how dangerous this individual is. She has tried to make me look crazy multiple times , said she will blackmail me and then 2 hours later tell me i should act right and earn her love.

im really struggling with this breakup, she told me she would leave me alone that she is sorry and she doesnt want me to feel this way. she sound genuine which is unusual for her. it made me think maybe she does have a bit of empathy, and the breakup went smoothly which is unusual also for our relationship, she messaged me after we broke up saying “ it was nice having your hoodie again knowing how you smell for the last time, take care” . i just responded with thankyou you too and no reply from her back. the reason im so on edge about this breakup is she has in the passed rang me on no caller id multiple times a day but will not say anything if i have picked up, she also would say she will show up at my door if i dont want to talk to her and block her and then will say she is just messing around . there is alot of mind games this girl plays and it can make me very anxious and overthink like crazy.