It takes two to cut a deal. Israel has to decide what is in its best long term interest. If Abbas gets reasonable, offering up something that takes into account Israel's physical and demographic security, and Israel says screw you however, it might undermine US support for Israel, and then the nation will be truly alone.
From what I can see, the only ones saying "screw you" here are the palestinians. Israel is bending over backwards. Mazen refused to disarm terrorists, his first obligation under the Road Map he speaks of so frequently.