Opinions?

I need advice/opinions on a situation. My bestfriend of 6 years is engaged to her baby daddy. They live together.

I absolutely adore my friend, we've been friends for nearly 7 years and have known eachother since middle school. The problem is that I do not like her fiance. I never have. He's disrespectful to her. He never helps with their child. He puts her down constantly. He even threatened to leave her and take their child. He's threatened her this way a lot, and he has called her so many nasty things on multiple occasions.

She knows what I think about him, she knows that I will never like him. She is my bestfriend regardless, and I'm planning to be here until she finally leaves him. Even if she never does.

Recently, he has decided to start attacking me whenever I come and spend time with my friend and have our children play together. It started off with him "jokingly" calling me a "thot" in random passing conversation. Now he's saying that I'm a whore, I'm self centered, it's my fault that I recently miscarried twice, and several other things that I just don't want to talk about.

I still want to be in my friends life, but I can not have someone like her fiance in my life and definitely not in my daughters life. I just don't know what to do.

My plan right now is to just avoid coming over when he is in town and to try and get her to come to my house without him whenever he's home. (He doesn't like her leaving the house and he doesn't like her having friends, so i try to come there as much as i can)

I don't even know if I want to try and go to her childs birthday at this point because of how much I dont want to deal with her fiance. (I'm going anyway, I'm not going to let her fiance ruin getting to see my favorite boy on his big day)

Anyway, does anyone have any advice or opinions? Do i just need to deal with it?