need moral support to leave bf

im not great in telling stories but please stay with me, i need helpso my(23f) boyfriend(22m) have been together for a little under a year and a half. when i met him he was talking to a lot of girl, and they knew and were okay with it. and he had talked about how he liked having all of them. but when we started dating i told him i wasn’t okay with it and he stopped. well fast forward a bit(like 6 months) and we lived together and decided we wanted to try for a baby. i got pregnant the first try, and we were both so excited. about three months later i had a miscarriage. it was really hard for both of us, but expeccally me. about two weeks after my D&C surgery, he told me he had gotten a hand job while i was pregnant, and it broke my heart but i decided to stay with him. during this time he started getting angry a lot, and he slapped and choked me a few times, but it was never that bad and he apologized every time. in the past we both happened to date the same girl( i’ll call her Dee). he dated her for 4 years, and i dated her for about 2 weeks. well a month later, i heard him on the phone and found out he was talking to Dee. and i was super mad and almost left him. but he convinced me to stay. i looked at his and Dee’s messages and they weren’t really flirting so i decided i could live with it. a few weeks after that he started telling me sense i’m Bi sexual, we should add another girl to the relationship, and when i said no he told me i wasn’t really bi then. and he never dropped it. my bf is kind of famous, you wouldn’t ever recognize him on the street, but he has a surprisingly large fan base. the past month. he decided to start talking to all his fans. getting nudes and stuff. and it once again, broke me. but i chose to stay still, because it was just messages and i figured he’d never actually meet up with them. he always told be he was in love with him and i was his queen. well i just found out he wants to have one of those girls over, and he wants to sleep with her in our room on our bed, and have me stay in the guest room. i have never felt this horrible, i feel disgusted with myself for letting him treat me this way and letting things get this bad. i feel pathetic. and i know i need to leave, and i really want to leave but i’m scared i won’t be able too. my plan is to leave while he’s busy tomorrow but i’m scared i won’t go through with it and i’ll end up ruining my life staying with him.