Wow how painful this all is- and a lot more complicated than this post but I would could write an essay!
Sis is my best friend (or so I thought) and I also love to pieces my now-ex BIL, with whom I also work. As families we have done lots together and we would have said that they were our best "couple" friends.
Sis left BIL after 8 years/2 kids, things just not working for her - no nastiness in relationship but she was desperately unhappy.
DH (who has become very good friends with BIL over the last 8 years too) and I have maintained from the start that we will try and keep out of it for as long as we can but have known that eventually there might come a deciding point where we have to make a choice about where our loyalties lie. I have been able to remain fairly close to both (less so to my dear sis, more through her distancing herself though than anything)
although DH hasn't really seen much of her but lots of BIL.
The rapidly souring situation between sis/bil is starting to come between dh and I now, if forced to choose between the two my loyalties will always lie with my sister no matter what I think of her situation or behaviour (within reason of course, no illegal/highly immoral activity going on though!)
I've tried to remain as unjudgemental as possible of either individual (I'm sure that both of them get enough of that from their other family and friends) but DH, being one of these "It's just not logical Jim" Mr. Spock sorts of men who only see things in black or white is totally siding with BIL. (Plus dh has had a rough time himself over the last year and so has really appreciated BIL's friendship)
We agreed a while ago that in matters of each others family, he would have the final say in how we dealt with his and I would have the final say for mine. (If there was a strong difference of opinion.) I guess I am really hurt that DH hasn't followed through with this, I fundamentally disagree with the way he has determined we should deal with a family matter in his close family but stepped back, and now he won't do the same for mine. I am shocked at how much I feel let down by him. Grrr! I suppose he just feels more strongly about this situation than I did about the previous one, but can't see how this is going to get resolved well.
Help!