Chronic side pains and blood in vomit?

My girlfriend has been complaining about a re occurring pain on her right side( close to the hip , parallel to her belly button ). I can tell she is in a lot of pain and the other day she told me she threw up blood, last night she could barely fall asleep and would occasionally pass out for a few seconds ( not fall asleep. Pass out.) I keep trying to take her to the doctor but she's stubborn and won't listen , what could this be?