I really do need help here.?

i would have a chat with her mom. bring her a nice card or something, and give your condolences. tell her how much her little girl meant to you, and you'll miss her. give her some background on your situation, and say that the ping of your mother is hard for you to deal with, and you don't think you can bring yourself to go to the funeral. tell her you're there for her if she needs you (and live up to the promise).