J.N.
It sounds like they have deeper issues than what happened with your boys, probably stuff that has nothing to do wih you. It's just easier to blame someone else than look at their problems. In all honesty, it's not really your business if she's depressed or he's hiding in the bottle. But maybe they are asking for help in the only way they know. You may want to talk to them when things are calm and just say 'we heard you're selling your house, we'll miss you, is there anything we can do to help out?'
I would suggest trying to stay in contact with the kids, but be careful to not be seen as 'turning them against their parents'. It also depends on their ages - teens are a lot easier to stay in contact with than younger kids i think.
As far as your boys apologizing, it may have been appropriate at the time to have them apologize but I'm not sure if there would be any lesson in that now. And totally ignore the advice the dad gave you about raising your kids...but then i'm sure you know that.