my ex hates me im convinced

we broke up a couple months ago nd i thought we came to an understanding but she keeps on finding some way to talk shit about me to her friends or anything like that , and i genuinely don’t think she’s a bad person but i don’t know why she’s acting like this i genuinely am trying to better myself and i’ve accepting the wrongs and i’m trying to improve but it’s like she’s just bringing me down but by bit everytime i have ONE accomplishment ts not fun man. i don’t hate her but i’m just disappointed in the person she’s become

and P.S. i didn’t cheat on her or anything i just wasn’t a good boyfriend :/