I have to agree with what others have said. He has not prioritized you, and he has not thought about the effect of his actions on you or his daughter. To stay in a relationship like that is toxic. It's painful. Something like this can take it's toll. I'd be afraid that it will make you emotionally unavailable to your daughter, to be the best mom you can be. Depression is a life sucker that does not only effect you. You deserve better.

I have to say, I'm sure it would be easier to do now, four years in, then later. Things only get harder and more complicated as time goes by.