Why can’t I leave him

I’ve been with my boyfriend for 4 years we have two children we are both 22 and I’m too scared to leave him I no how he treats me is wrong but how do I get the courage to leave? We will call me a useless mum that I don’t care or love my children witch is far from the truth my kids are my world I work part time he does nothing won’t watch the children while I’m at work my mum babysits then witch she loves but it’s not the point their dad should want to watch them. He has both my bank cards decides what the money gets spent on any chance he has to humiliate me or make me feel alone infront of people he will he will call me fat worthless stupid the list goes on sex is even on his terms i feel like I’ve lost myself I don’t no who I am anymore the right thing to do would be kick him out the house is in my name but why can’t I kick him out what am I so scared of I really don’t have a clue I feel so stuck and fed up but I can’t tell him to leave what is wrong with me? Maybe I do need him around otherwise the kids would be stuck with a useless mum please help me it’s like constant battle in my head I’m so broken 😢😭