There is always hope. Sometimes it is all we have. Standing and for how long is a decision you have to make for yourself. You need to think of it as, do you really want to be with someone who can treat you with such disregard? The dirty work - he filed it, let him follow it through. All you have to do is protect yourself and your family. Don't participate with the D in any way other than you have to by law and to protect yourself.
Unfortunately, the best way to relay to others that it is not your fault is to do nothing. He's going to blame you for his unhappiness as long as he stays in the tunnel, regardless of what you do. Actually, it's not about fault, just maturity and responsiblity. Take the high road, but pick up a few rocks from the low road, just for protection.
