My son left his wife 11 yr old daughter and his two stepchildren, he behaved very badly, I was devastated we fully supported our dil and the children, we were always grandparents to his step children, he was with somebody else, I hated her and totally sided with my dil.......move forward 6 years my son married the girl I hated, they have two beautiful babies, my step grandchildren have cut us dead because we have contact with our new dil, their mother has remarried ,we were so close but her new man didn't want anything to do with us, so she also cut us from her life, I cried constantly and ended up on anti depressants, my GD is now 17 and we have a wonderful relationship, I'm still struggling with the loss , I think you'll shed many tears but do try to distance yourself from their problems and concentrate on your DGD, don't be like me and take sides cause I ended up the one that was terribly hurt, I wish you well 