Here's where I disagree a bit. I think people shouldnt stay in a miserable relationship. If they weren't married with Kids then get a divorce which is an easy solution. The kids make it tricky but alot of miserable relationships kids do notice and are effected by. For the kids the parents shouldn't divorce or separate but they also shouldn't be miserable which effects the kids. So at that point the relationship is over and you just need to decide how you should handle it. A civil divorce which should include family activities like a scheduled dinner every 1 or 2 weeks. Basically they should be trying their best to have as much of a family dynamic for the kid. Perhaps an open relationship could work. Before all of this the parents should try couples counseling if at all possible first.