Anger is a great tool to help with detachment. So while it's clearly not as good as happiness, it's probably better for you than depression!
Now, if you wanted to get rid of anger... you might want to remember that husband really hasn't done anything 'wrong'. He's an adult. He has every right to decide he doesn't like you and end your marriage.
Sure, that decision is causing you extream pain. But it's his right. If anything, he is being more civilized than most WAS on this forum (no OW and he isn't hurling pain and insults at you like other folks).
The sadness\regret are one emotional extream and the anger is the other extream. You swing back and forth, with the hope that you can settle down into the middle (ambivalence). That's the final destination of detachment.
My thread, Carpe Diem #4 Orig Thread: Carpe Diem #1