So sorry that your daughter has a bum of a dad.
I would guide her that it is IMPOSSIBLE to change him, or get him to be the dad she wants him to be and that as much as she wants it, it isn't going to happen. If she goes through adolescence trying to work through this (and being unsuccessful - as we all know she will, because he isn't going to change), she will end up with someone just like him as a husband.
Instead - work with her on the fact that other peoples problems are not her fault and that NOTHING she says to her dad will make a difference. He doesn't care or he is so overwhelmed with the failure of that relationship that he's trying to find another one that is perfect - instead of realizing he is (at least part of) the issue.
I wouldn't advise her to tell him how she feels. About anything. He's proven that he doesn't care. So, teach her how to morph her current (dysfunctional) relationship with him into something that is not so damaging for her. Help her grieve for the dad she wishes she would have had and then get over it and move on with her life. Help her find relationships that are positive and healthy toward which she can put her time and attention. Help her to understand that people don't change and it doesn't mean her dad doesn't love her. It means her DAD is incapable of having a healthy relationship.
Help her understand what a healthy relationship is. Model it for her with your relationship with her. help her to understand that her time and energy and valuable and that she has a CHOICE of how to spend that time and energy. If she spends it trying to change him with her emotions - it will be wasted. If she spends it doing things she enjoys with people who love her - it will be remembered.
Have her de-friend him on facebook. She shouldn't have access to his social networking site. She ISN'T his friend. That's not a healthy relationship for her to be in..... teach her to how to let go of someone when they are not who you want them to be. this will help her when her boyfriends are "perfect.... except for xyz, and she stays with them, feeling that if only she got the courage to tell them how she felt it would make a dffierence". Help her to learn that xyz WON'T change no matter how much SHE wants it to.
Teach her how to accept someone (anyone. even her dad) for who they actually ARE and then be strong enough to decide IF THAT IS ENOUGH FOR HER. if it's not, teach her how to let go.
This is crappy stuff. I wish her peace.
-----------------------------------------
ETA: I really like what Angela S said about being honest with her that you made a mistake in picking him. This is a great chance to help her understand how to make choices. The lesson isn't to focus on your mistake in terms of what a jerk her dad is.... it's about the process you use to select your mate and what to look for in the people who we let into our lives - give examples now of people who you have thoughtfully and purposefully chosent to (or not to) let into your lives. This won't knock you off your pedastal, instead it will elevate you in her eyes to someone who is self aware and learning from your mistakes.