Mighty, it isnt right and it suckks big time, but, it's what they do. It just is.
Unfortunately your daughter has to realize she cannot count on her dad. Tough lesson to learn, I know, but that's how this goes, sadly.
The sooner all of you realize that, the better off you will be. He is lost and in crisis. Not an excuse. Just an explanation.
I know it hurts to see your daughter upset. And I know it isnt fair that you have to have all the burden. But you are their touchstone right now, their rock. And truthfully, at least for me, I was honored to be it. It is his loss, M. All the way around.
Please dont allow his actions to adversely affect your life, hard as that might be.
Mighty, Please read and re-read what uRworthy has posted. I totally agree w/her because you and your children can't rely on him for anything. He's gone, out to lunch, or is acting out as a teenager. Believe it or not, but your kids are more responsible and more mature than he is right now.
If it will help you, think of him as another teenager from down the block who can't get his stuff together. You have to try to find a way to not allow his actions to adversely affect your life. Unfortunately, this "baby" is going to be around for a very long time because of the kids. Find your center, breathe and let it out. He's not worth getting upset over.
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.