We're Headed For Divorce.

My mother in law has been a nightmare since my husband and I got together. First, a disclaimer: My husband and his family went to our church and we grew up together. We hadn't spoken in years and then his little brother, who was 17 years old, passed away suddenly. It would be a year until Steve and I would get back in contact after seeing each other at the funeral. I say that to say I get that Steve was her only son now. She didn't like us dating and didn't realize we were really serious. When I got pregnant she denied it was Steve's baby and continued to believe that. I almost lost my baby at 7 mths because we thought he'd be born permaturely. She thought I was really 9 mths and called to tell my husband not to sign anything if I had the baby. We my son was one she brought a needle home from her job. My one year old found it and pricked his tongue and we had to take him to the ER. She got mad at me when Steve got mad at her for bringing it home. I was pregnant with my second baby which was an at risk pregnancy and she tried to fight me. Through the years she's caused a lot of hurt but the last straw for me was her blocking my car with hers and waiting for me outside when I was about to go to work. She waited for an hour outside then left. When I went to my job she was inside so I rushed home and went in the house. She came back then waited at the car for 30 mins before finally leaving. My husband still wants her to be apart of the kids life and I don't want her near my family. Am I being unreasonable? She can see Steve whenever though. I just don't feel comfortable. Like that's not even close to everything she's done. I don't know what to do.