My soon to be ex-wife terrifies me

Kate and I got married this year. Almost 2 years ago, we had our son, Lucas. I think I married her because I thought it would be right for Lucas to have a family that was together. Slowly over the course of our relationship, I started to realize Kate would spend nights screaming at me. Most evenings, she would make me serve her. I would have to drop whatever I was doing to get her things, whenever she wanted. She would spend most of my money (she doesn't work) and then lecture me about how I need to be better about spending. I smoke weed, and she would call me stupid and a bad father, even though I love my son and he loves his dad.

We decided to split up. She said I wasn't having any sex with her and that we want going to work for her. I admitted I wasn't ready to be a Dad and I didnt like being around her

I moved into a friend's house temporarily who was also her friend. She keep threatening me with legal action even though I am willing to give her way more than a court would make me pay to provide for her and Lucas. She doesn't want to give me any custody.

Why did I marry this terrible woman?