Wow, like so many others have noted, I can TOTALLY relate to this extremely painful ordeal.
I am experiencing it right now actually, with someone that I have known for a very long time.
I was with her at her ultrasound when she was pregnant and her awful husband whom she later thankfully divorced, couldn't be bothered to go and be with her. I was with her when she had to have a medically induced abortion years ago due to her extreme debilitating asthma. I. Was. There.
Here's the thing: I have begun to realize the many times that she has not been there for me, not really.
Hence: the ghosting, the haunting, as it were.
I don't know what has happened. I wish her no ill will but at the same time, I am also hurt beyond belief.