Need advice about lying SO

Okay ladies I need ya'lls help I have known this guy for 9 years been together 1.5 years and before we got together he was so shy and quiet and you would never think in a million years that he would even know how to lie but I was wrong....when we first for together he would lie to his mum about where he was..he would never tell her he was with me, he would go out of the room every single time his "mum" called but I started suspecting it wasn't just his mum on the phone because this mutual friend of ours would tell me things in detail that only she would know if he was talking to her (they have history) and he lied about talking to her and having a past...fast forward to 2 months ago..found sexts on his phone to another girl,he lied about it initially than admitted after I told him I had the conversation translated into english (he speaks spanish and Portuguese) he had proposed to me around the same time. 2nd girl he was telling her how much he loved her and wanted to be with her, lied about her too, 3rd girl, 4th girl same thing. Now the 5th girl he actually went over to her house 2 days after I introduced him to my family, he claims they are just "friends" (I've seen pics..not true) and he suddenly cannot "remember" why he went over there...so I know I'm going to get alot of leave his ass and kick him out but he refuses to leave saying "Its you or nobody else" and "you belong to me" he did get in my face a few days ago and threatened to punch me but I honestly could take him down with both hands behind my back but Im basically asking what would you do in this situation? Thank you for taking the time to read my long ass post