Had a number of friends split up over the years. Been saddened by it and been happy for one or the other or both. Been there done that twice myself. Was saddened by the first divorce, overjoyed by the second one. Kept friends, lost friends in both cases.
I've remained friends with both, sided with one or the other and became enemies with one or the other, on a couple of occasions both when I opened my yap and tried to offer an objective counseling to both, thinking I might help them change their minds and work it out (don' do that no mo).
Back in college a couple in our circle of friends split up. Some of us guys were sitting around BSing and Steve says, Peggy and I are getting a divorce. We all sat there, a bit stunned. Then wise ass, insensitive, bachelor Mike blurts out, Hey, that's what ya get for gettin' married! Not cool but poor forlorn Steve was the first one of us to crack up laughing.