Name-changed to protect the guilty.
DH and I have been married for nearly three years and we have two children (2yo and 4mo).
My FIL is a horrible man. Ninety-five per cent of the time, he is terribly charming, always polite on the surface, but actually he is a deeply racist, misoynistic man. MIL has been worn down by him over the many years and has no opinions of her own, is shouted at if she tries to say anything different, treated like a slave, etc. She has no friends and doesn't talk to her family anymore because of FIL meddling. (We keep up with her side of the family, but FIL hates me us for it.) She's also not always very nice to me, but I know it's because FIL doesn't like me.
DH is the second of four boys. It is only since we got together that he has started to work out what his father is actually like. He no longer defers to FIL's opinion on every decision we make, unlike the other three sons. He also understands that the way FIL has treated MIL their whole married life is beyond the pale. He still finds it very difficult to stand up to FIL though, although we have made some progress over this last year.
I have never witnessed FIL being violent, but I have seen him have violent outbursts when angered (usually because MIL has dropped her fork, or answered the phone wrong, or not cooked the potatoes the right way). (This have never happened in front of our children.)
DH knows that the first time he has one of these outbursts in front of our children, we will be leaving immediately, and I will never allow my children to see FIL again. I would actually like to never see him again NOW, but DH doesn't think that's fair as FIL is always lovely with the kids.
However, I have just discovered that FIL once hit MIL in front of the boys when DH was about 9yo. MIL's sister told me, and when I asked DH about it, it became apparent he had repressed the memory or something. He got upset and told me it was the worst moment of his life, but didn't really understand why he'd never told me himself. He said he hadn't thought about it for years and years.
After FIL hit MIL, she escaped to her family with the boys in tow. FIL followed and told the boys to choose between her and him. They all chose him. I assume out of fear, but also he has this weird hold over them all. None of them respect MIL even now. Anyway, as they all chose FIL, she went with them, scared of losing her children.
She was an alcoholic their entire childhoods, which upsets DH to this day when we talk about it. I think her alcoholism caused a lot of the arguments between FIL and MIL as the boys were growing up. I assume being married to this horrible pig was the reason she drank, but I find it hard to forgive her for driving them all around drunk every day. Actually, I blame FIL entirely, but I wish MIL had been strong enough to protect herself and them from him.
This is so long and complicated, and I haven't explained half of their awful family history and problems. But I need some advice; I have no one I can talk to about all of this. Now that I know he was violent at least one time (and I doubt very much it was a one-off that happened to be in front of the children), surely I can say to DH that we are not going there again? I don't want to put my children in danger obviously. But DH won't accept that we won't be visiting anymore, I doubt. How do I persuade him? How do I help him?