Please help! I can't take this anymore?

Google "Borderline Personality Disorder".... Where is your father in this? Do you have any other family members you can talk to? Whatever disorder she has, it sounds serious enough to where you should have some outside help - either family, counselors, a doctor - SOMEONE you can talk to and get help. She won't seek help until something scares her enough to snap her out of it and realize this isn't normal. The best thing you can do for her is to talk to someone and have them guide her to help before she winds up in the emergency room.