Hi everyone i am very new to BPD, by this i mean i recently started a relationship with the most beautiful young lady i could imagine, and she has BPD. 
I have read alot of conserning things about bpd and relationships on the internet, for example that they dont last and that people with BPD are more likely to cheat, i always ask her about these things when i read them, but she always denies the negative parts and says she wont/dont do that. Trust me when i say she is the most loving person and i have never felt so much for someone as i do for her, but.. Recently in an argument she said she cheated on me and after the argument she said she only said this to hurt me, she also used to talk alot behind my back to one of her closest friends until i asked her to stop, she also called me ugly and fat, but when i told her i didnt like it she stopped, she also said «maybe i should cheat on you» stating «you act like you want me to» i just want to know if things like these are things i should take seriously, i have read that setting boundaries for what is okay and not is important and i try my best, i really want this to work out so i am asking here for help, thanks for all answers :) please Ask me if there is anything else you want to know around the subject as i know im not the best to write long paragraphs and this is my first time ever writing on Reddit