I guess the important question is, how amicable was the divorce? My brother got divorced from his first wife when my niece and nephew were 14 & 16. They are now in their 40s and both parents are remarried and they are all one happy family. My ex-sister-in-law's new husband thanked me for being so nice to him. I told him I had nothing against him, that both my brother and sister-in-law were much happier divorced than they ever were married. Only you can decide whether you want to help, but I would say if you want to be a hero in your daughter's eyes, then put aside all animosity and quilt forward. The past is the past, time to move on.