Having been in two relationships with men who both have children to a previous partner (that includes the one i am in now) i can honestly say amalgamating two families is an absolute nightmare. Their kids, my kids, their parents and the rules that the other mother father grandmother etc impose on their kids etc well its a recipe for disaster. After the first relationship i swore blind i would never do it again yet here i am. I have kept a very wide birth on my partners kids (11 and 9) but also my two (27 and 25) have their own set of inherited from their father behaviours! Me and other half have been to therapist to try and find a way through (which with adult kids i really do think it beggars belief that there are still bloody issues to deal with!). No advice to give other than go to therapist and discuss and dont drink! May the force be with you.