i was in a similar situation 15 years ago, i had one months wage in my bank account and an awful heavy fear suffocating me into thinking there was no way out. There was. I remember having a panic attack, i couldn't breathe, i couldn't move and i couldn't think. i just froze. l stopped thinking about how much stuff i could move out without getting noticed, how i was going to get everything else out, what was going to happen after i did, how i was going to handle it - everything. A strange kind of calm came over me, i saw myself getting up and picking up my handbag, my coat, put my shoes on, look around, pick up my phone, charger, put my windchime and dreamcatcher in my bag and then walk out of the room, down the stairs and out the door. i didn't remember the journey to the pub, or texting my friend to tell her "im not going back. i don't know where to go'. thankfully, like you i'd already smuggled my most precious posessions - paperwork/passport, my journals, school yearbook and the only pair of decent clothes i had, to my friends house two months before. it was the scariest thing i've ever been through, i had to get help for ptsd 2 years later cause even though i was free and safe and was 'smiling all the time', inside i wasn't there.
you can't talk, reason or do anything with this person, it won't work. you just have to get out and then you never have to see him again. it's ok to feel the fear, you've already taken care of the paperwork, if you want to you can just grab your bag and the dc and walk out the door to your sisters house. everything else is replaceable, and/or you can go back with
friends or police escort to get the rest. Don't think about what he's going to do afterwards - keep your focus only on you and your dc.
i'm sending you a massive virtual hug and raising a glass of mango juice to your success-TO FREEDOM! [GRIN]