He said his wife’s brother is going through a very nasty divorce that is threatening his 17-year marriage. He says too many things have gone wrong when he’s tried to be a friend to his brother-in-law for him to want to be friends with him and his new girlfriend. He and his wife are unable to come to acceptable terms about the situation.
I said:
I’d have to guess that you really liked your sister-in-law and think she is getting a tough deal. I’d also guess that your wife would take her brother’s side regardless of the circumstances, which is quite normal. If I’m correct, both of you would be justified and deserving of your feelings. But those feelings and opinions should not interfer in your marriage.
Let me suggest that you do everything you can to overcome your animosity toward your wife’s brother. This is simple logic. He will always be her brother, and as long as the two of you are married, he will always be a part of your life, either good or bad.
This is your choice, your decision. You can decide to “forgive” him for having been a jerk. You don’t have to forget that he has been a jerk. (He might still be a jerk.) Just don’t forget that he is your wife’s brother, and her feelings toward him are valid and will not change. It can only cause dissention between the two of you if you try to make her “choose” between her brother and her husband.