Jacob promised not to tell her father about the motorcycles, because her father hates them. And when Jacob told him she was upset and said he had betrayed her. He did this because he was upset about Edward coming back.
You need to put in why Bella leaves her mother. Her mothers new husband is a baseball player and they have to travel alot and Bella doesn't want to travel. Also Edward isn't repulsed by her. Her blood smells extremely good to him and he actually doesn't want to and can't hurt her. Theres more...