My ex SIL remains on good terms with my DD, and the rest of our family. Drink problems caused the break-up, but my DD has always spoken well of him to the children. His own family have always looked on him as the man who can do no wrong, and been rather offhand, even with the GC.
He is now a reformed character (as far as I know) and is engaged to a very nice lady. The wedding will be in Australia, so attending it would not be an option. If I was invited, though, and could attend, I wouldn’t hesitate to go. My DD also wishes them well, and hopes that he has learned from his previous mistakes.