HEAD OR HEART? HELP!!

so i was dating this guy for over 2 years, we split due to me being scared that he’d cheat on me in uni (he was texting other girls and his mum “banned” me from being up there and he followed her). a week before uni we split, he went and i already had a problem with a girl, she’d barge into his room during our facetime calls and listen in and then speak to him/run about after him. i didn’t like her, he assured me it was nothing and she was just “mum” due to there only being 2 girls in a hall of 10. he promised me he wouldn’t get with anyone and he told me he still loved me, we facetimed and met up and then one day he stopped answering my calls. he came to see me and told me he’d gotten with that girl!! he says it was a mistake and has told her that himself, he’s also blocked her on everything too.

i don’t know what to do, i don’t want to lose him but i can’t get over what he’s done, he broke a promise but still says he loves. he says he hasn’t moved on and he doesn’t want me to either because he doesn’t want anyone else to have me but he won’t have me himself.

i’m pretty sure i still love him although i’m trying to tell myself i don’t because of what he did ... i just don’t know what to do :((