I caught my husband outside taking a girl

I left my husband watching our newborn and our 1 and a half year old while I stepped out to pay the phone bill. he called me maybe 20mins after I left and asked how long I would be taking I told him give me an hour. he than called again and asked me if i was closed by i told him 10mins in reality i was 2mins away when i pull up to the house hes outside talking to a girl. I lost it to the point where I didn't even get a look at the girl my main concern was my sons, why in the hell would you leave my sons inside alone to come outside and talk to another female. everything escalated pretty quickly, I asked for my car keys he refused to I put my hands into his pocket to grab them he held my arms so tight he left his hand print on my arm. he ended up taking my car and now refuses to give it back because it's under his name only because insurance was cheaper. words can't explain how hurt, betrayed, disappointed. point is I now have 3 little ones with no way to gety around my family says je should take me are I need to go till I get a new title and get my car back but my ego so big I can't see myself begging him for my favor. WHAT DO I DO?

I'm sorry let me clear something up I called it the house but we live in a building meaning that if any of the kids are crying he wouldn't be able to hear them and there shouldn't be anything in this world more important than your childs safety anything could happen at any moment so saying he stepped out for 2 min NO just like I don't know how long he was out there obviously no one else could possibly know. that conversation could had happen over the phone or when I got back and could watch the kids. and he has cheated in the past but we've been working on trust so I can't help but be on defense.