A, It's depression at it's finest. His actions, comments, sighs all indicate depression is hitting him a bit harder than normal. He's depressed because the mow isn't going to leave her husband, he's depressed because he's not happy and doesn't know how to turn things around, he's depressed because he's not happy w/his job, and the list could go on for another 4 or 5 pages. When they are this depressed, they just twist and turn because they are "frozen" and do not know how to find their way out of the dark hole. That's why it's important to just let them be and do not expect them to be themselves.
Your h knows that things aren't right within himself. He knows that he can't move forward or backward and that's why he continues to hold on to you and the family so tightly. He knows that as long as he's got that one string to hold on to, he can't sink any deeper in the muck. You are the lighthouse in his storm, no doubt about it.
One thing that I'm going to point out now that the week is over--when you phoned or tmed him about checking on your daughter and/or staying w/her, he may have felt like you were "expecting" him to be there. In times like this, I understand completely why you did it, but you will need to have a "safety" net for future emergencies. He's not always going to be up for this type of request. I know, he's your husband, but if they can't help themselves, how can they help us? This may be one fo the reasons that he has been acting a bit put out w/you. Just food for thought.
Over all, you sound good and I'm glad to see your children are doing better. I do hope that you've got something special planned for your special day. Leave the crazy making situation at the door and just enjoy the day for what it is--Mother's Day.
Happy Mother's Day!
Sit quietly, the answers will reveal themselves when you least expect them to. The past is gone, the present is a gift and you need to focus on today, allow the future to reveal itself when it is ready.