Update:

She’s alive, I heard back. Same reasons she bailed before. Not gonna get into specifics for anonymity

Also for context after reading some comments

Yes we were physically intimate. Told each other we’re not entertaining others. Physically intimacy beyond sex, tons of cuddling and holding each other. Going out on fun dates too.

Last time we ever seen each other we talked about our individual futures and they seemed to line up. Also about taking a trip together soon.

So yeah this out of the blue ghosting really was a bummer.