Well I don't really know much about Facebook, but if your friend has (quite understandably) decided to be invisible for a while, I realize it's been a very long and unhappy week of suspense for you, but maybe she feels she has to remain invisible for longer than one week.
After 16 years it's hard to believe she would do nothing whatever to re-establish contact. Could she, eventually, when she feels ready, establish a new Facebook identity, and then find you that way?
Not only do I not know much about Facebook. I don't really understand friendship too well, or so I sometimes think! So I'm not really qualified to say more than that you must continue to wait and hope. I know that's easier said than done...
If, as you mention, her father was also involved, then out of respect for his wishes she may be doing things in a way she herself is not 100% happy with and would not necessarily have chosen.
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You can't be proud of being Neurodivergent, because it isn't something you've done: you can only be proud of not being ashamed. (paraphrasing Quentin Crisp)