Hermes,
I do marriage counseling. I believe that one of the biggest things about a marriage is that the two people were probably married to each other in a previous lifetime, and they are just "picking up from where they left off" last time. (Of course I don't say this to couples.)
I believe that a lot of marital troubles are continuations from troubles they had together in a previous lifetime. I think that, for many couples with difficulties, they are just continuing with problems from a marriage(s) in previous life(s) together.