Hello D S,
I had the same issues but with my MIL, FIL and one of the SILs.
My husband and I decided to go to a marriage theapist. Which was great. She showed my husband that I was feeling second rate to him, that I didn't matter, but what he should be doing is making me his top prority.
But, she also showed me that that is his family and I should not get in the way of him seeing his family, just I don't have to go.
To be honest it was hard at first. We have a 3yr old son, and I wanted my son not to have anything to do with his family as I know how much they hate me and would do things to our son just to hurt me.
But, I had to have faith, yes faith, that they would screw it up on their own at one point. So, I would put on a smile when I had to see them like birthdays, holidays, etc.
Well after 3yrs (these years where only after my son, but the hatred started in 96') they screwed themselves.
On Thanksgiving 08' my MIL screwed herself big time. My son, husband nor I have spoken or seen them since. Well my husband one time just to let them know she will not have a relationship with us again.
Quick history....we have never left my son alone with my Inlaws, never!!! Even when we visit (we live just 6miles from each other) we are always in the same room as them both. But, my MIL does hug and kiss him and she whispers in his ears. We gave her the benefit of the doubt, that she was saying she loves him, etc.
Well Thanksgiving evening my son started to act out, telling us he hates us, he hates my parents , etc. We spent the morning of Thanksgiving with his mother and the evening with my family. When we were getting ready to leave to go to my family our son just refused to go, but my husband said do you want to go to Nana's. He smiled and said yes and started to get dress.
So, we knew something was up, after 3 days of role playing and talking to our son. He broke down...my MIL told my son to hate me and my family. That if he told anyone that she said that, that she won't buy him things and that his Daddy would get in BIG (and he stressed BIG) trouble. Our poor sweet 3yr old boy was so scared that his Daddy was going to have to go away because he told me what Nana said. I was smart about when my son and I spoke because I had my husband stand in the hallway to hear everything that was said. So, he heard it with his own two ears.
Boy, the Inlaws screwed up. Our marriage has been wonderful since Thanksgiving and our Thearpist said we don't need to see her anymore that we are doing great.
So, the advice I have is see a thearpist and remember the Inlaws will screw themselves soon enough!!! And when they do something don't tell your husband unless you have solid hard proof!!!
Good Luck,
M.