I had a friend of 20 years who did not return my call after my mother died until after the funeral. She then said what a bad friend I had been since I kept changing when I was supposed to drive cross country back home with her. I changed the date because I was caring for my terminally ill mother and could not leave till she passed. It tells me that your "friend" may not be healthy for you, just as my "friend" was not healthy for me. As you allude to friends should be there to support you not to drain you. Don't put too much energy into it, she's taken enough from you already.