We can guess why someone ends a friendship but never really know unless we ask.
I am about 30 years old and a friend of 12 years, who was around for all of my major life changes, suddenly cut me off. I thought maybe she figured my wild phase was not a phase, but we all had our phases and they've passed.
Then I thought maybe she was convinced I was a creep because I had explored my sexuality in some interesting ways when I came out of the closet. She was someone who accepted me at the time although we'd been purely just friends for a few years after that. Then I thought maybe she's embarrassed that she was my friend. But all of her friends knew we had been close for years. Her husband seemed to like me, but maybe that was the problem. Or that I used to get paranoid and talk about my problems too much (??)
I just hold onto the hope that she realizes people change and would like to have me on her Facebook again, or some kind of minimal contact, along with my other old friends. She did always have a weird belief (I'm on anti-depressant medication) that no one has "diseases" and that everyone has enough will power to be "normal."
So because of all of this, I'm not surprised in a sense that she might do something like this. I always block the subject out, but then she started befriending the other friends in our old group and not me. I don't think I'll ever get over wondering what's wrong with me for the rest of my life to have a good friend of 12 years just completely cut you out of their life. Hmm.
Sounds like you answered your own question. Friends often drift apart and you have raised several good hypotheses about why this friend may have severed ties with you. If being cut off or dumped isn't a consistent pattern in your relationships, don't focus on "What's wrong with me?" Instead, presume your friend has cut you off for reasons that have more to do with her than with you. She may be more concerned about burying her own history rather than with dumping you, per se.
If you really care about this friendship, you could try calling or emailing to see if she's open to getting together. This is probably more direct than the Facebook approach. If she doesn't respond, you'll know you tried and can move on.
Hope this helps.
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