Why does he always have to fly off the handle?I have been with my boyf 9 years, we have a 20 month old son and

another on the way. I love him very much but he always finds a reason to scream at me. We will have 3 lovely weeks and then a terrible arguments - basically with him shouting in my face calling me a psycho.When I first started this relationship his mother hated me, I tried to please her and wanted to get on with her but It was if she thought I was not good for her son and always made snide remarks etc. I did nothing to her for her to not like me, she just didnt for some reason.As the years went by I started to dispise the women. Her remarks had started to wear me down and I was getting older and wondered why I had to take this kind of abuse, to begin with my boyfriend would agree with me, but I think him and his mother used to be close so it was hard for him if I ever said anything about her.Since my son has been born I have accepted her, she treats my son well and is nice to me and I do genuinly like her now but if I ever say anything about her he screams at me....why?? Does he loveme