Fiancé won’t let us break up

Help 😫

What do you do when your fiancé/father of your child won’t let you break up?

We’ve been together for 6 years and I think at this point I’m so unhappy that I’ve started to resent him. He’s an amazing dad, just not an amazing partner. He’s not cheating or abusing me, just so many little things that have added up over the years. I keep begging him that I want to break up but he keeps saying that he doesn’t want our son with separated parents, which is valid. But my response to him is always “ok so you’d rather him grow up listening to his parents fighting and raising their voices every single day?”

Like he literally won’t let us break up and I’m absolutely depressed and i don’t know what to do.

Edit: I can’t pack up my stuff because it’s my house that I bought by myself and every time I try to kick him out or ask him to leave he pulls the “ok then give me all the money I’ve put into the house” card, which is just half of the mortgage each month.

We’ve also sat down and talked and I’ve told him that I think since he grew up in such an unstable environment at home, this is his only sense of stability and he’s afraid of what’ll happen if we break up. He literally has nowhere to live and makes shit money at work and is so bad at saving money (I’m so good with money and he has multiple collections and racked up credit cards- that’s why I told him that we can stay engaged for as long as it takes and I refuse to marry him until he fixes all of his financial problems) so he can’t even afford an apartment.