What would you do?

The biological father of my 8/6/2yo apparently bought a whole house behind my back- 3 times the price of the one we live in..

When we met 10yrs ago his ex wife had cleaned him off- he was broke/depressed/300lbs. I put all that behind and fell in love with him! 3 kids later he’s figured out that we’re not compatible and doesn’t love me anymore.. great! He’s got $$now and lost the weight!!

He’s basically given me the silent treatment since March! I don’t think there’s anything worth fighting for as now that I analyze this decade- the fact that I gave up my career, disturbed my originating family to help raise the kids who he sees 1hr/day max! I’m over him but what sucks is him turning the older kids against me every chance he gets he tells them “I want to do fun stuff with you but mommy won’t let you..” so they’re constantly at odds with me.

9 out of 10 times that he’s with the kids one falls/cries his relationship with them is odd like he’ll put his behind in their face and fart.. they’re girls- it creeps me out , they laugh!

He’s always the victim and uses the word “abuse” as in I’m abusing him.. meanwhile I have no access to cash! The car I drive is his- he knows every move I make. The house his and we’re not legally married ( he broke the engagement after baby #2 and made baby #3” so I wouldn’t have another kid with another man “-his words!) He’s said to me all he wants is to visit the kids but he’s a backstabber and he’s already ordering kids furniture at the other house! I’m scared because he’s emotionally unstable he drinks/smokes weed potentially steroids too and he’s off looking at him. He cannot hold a conversation only switches to fighting which I walk away bc what’s the use..

Hope to get some feedback from whom has been in this kind of mess. Thank you!