My girlfriend does not want me to accompany her on doctor visit?

My significant other has been ill but undiagnosed for sometime. In the past week she had a small mole removed from her leg. She was told it is melanoma and is scheduled to return to have a "core" removed for further testing. Coincidentally, she recently had blood tests in a process of identifying the cause of abdominal pain. Today the doctor told her he needs more blood tests but that he needs to see her in the next few day to "discuss" her case. She is extremely concerned that the melanoma and the abdominal pain are related. I know she is afraid and worried about this upcoming doctor visit. I told her that I want to go with her to the doctor. SHe said no. I insisted. She said NO. I need to go and be with her! How do I proceed? Thank you!