Dear Gru
I rented a room in my home earlier this year to a guy who claimed years of sobriety in AA. After several weeks, he was picked up on a DUI. I immediately drafted a 30 day notice to vacate, had it notarized and served him. I also gave a copy of the notice to a trusted friend in case I ran into trouble.
The guy got a second DUI two weeks later. He left my home by the date I specified and moved out of state. Last I heard, he was homeless.
During this process, I felt fear. I think anybody would. Sometimes as family members, the abuser used fear to control us. I realized this quickly and rose above it so I could "conduct business" and get this guy out of my house.
If you can do the same thing and get your ex out, you will quickly feel stronger and better. It is like having a gigantic splinter removed.