I can't fault the father of the boys. He took care of his kids. It doesn't sound like he's got extra, as it ought to cost a lot more than $1800/month to live in HI.
My complaint is sort of a opposite: A good friend at work's ex-wife got caught cheating on him, yet got custody of the early teenage boys, and alimony. She now lives with her boyfriend and the kids, collecting alimony and child support while he, on a >$120k/year salary, can barely make ends meet because he has a condo in the same town that she moved to. And yeah, he'll be alone for Christmas. The moral of the story - never get a divorce in Massachusetts if you are a guy.
Edit: Oh, I should have mentioned this - that was a beautiful thing for you to do. My hat is off to you.