Relationship help

I’m so upset and need some advice.

My boyfriend and I have a 6 month old baby. Before I got pregnant we had a big party life style. We both have good jobs and earn good money, every weekend we would party and spend lots of money on drink and cocaine (its so normalised where we live, everyone does it at parties and we just got sucked into it i guess). We always said if we ever had children, that would fully 100% stop as I dont agree people doing drugs when they have children.

We had a few incidents when I was pregnant with him still doing drugs behind my back when he was out drinking with his friends and I was really upset when I found out and threatened to leave when it happened. He would always get really upset, say how disgusted he was with himself, say he struggles to say no to it when drunk and it was always “that was my last blow out before the baby, i wont do it again” blah blah blah.

Fast forward, baby is now 6 months old. We’ve just gone away to stay with some family for a long weekend. We all went out for a family meal, and they all started drinking. I didnt drink as I haven’t touched alcohol since the day i found out i was pregnant, just doesnt interest me at all anymore. I didnt mind him drinking as he was having a good time with family. We all went back to the house and they carried on drinking till early morning. I put my baby to bed in the room we were staying in and then I stayed up with them all, (still staying sober but i partied with them as i wanted to still have a good time with them. It got to 4am, and my boyfriend then started telling me to go to bed as he felt bad i was the only sober one. I said i was fine, i was having fun, baby was asleep upstairs, i kept checking on her, but happy to still stay up with everyone. But he kept insisting i go up to bed. I got a bit upset and said fine ill go to bed. I come downstairs quickly about 10 minutes later to grab some water and hes doing drugs (which is obviously why he wanted me to go upstairs). I was so upset and when my baby woke at 6am, i packed up our stuff and said I was leaving (about a 10 hour drive home). He got really angry and went to put his hands round my throat, and was totally drugged up. I forced him into the car and drove home. He spent the whole car journey home hallucinating and vomiting so I have no idea what drugs he took.

I’ve now packed up my stuff and moved into my parents house for a bit as I’m so upset.

Hes very upset as well, and was literally on the floor crying and begging me for forgiveness and begging me not to go. He said its the first time its happened since having the baby, he said he went way over the top and was so drunk and couldnt control himself when everyone around him was doing drunks as well. He seems so upset with himself and begging me not to leave him and take the baby away, and I’m so torn as other than these odd occassions this keeps happening, hes the most perfect boyfriend and Dad to our baby. So i just dont know what to do.