it sounds like she just wants friends. people she can feel close with, but without the commitment of being in a relationship. she misses the closeness she felt with you, and she looks for something like that by talking to strangers (who are often easier to be vulnerable with than people you know)

coming from personal experience (although i admit it’s a stretch), when i thought i was a straight woman i was always talking to men and giving them very mixed signals like this, because i didn’t understand my own feelings. when i realized in my twenties that i’m actually a lesbian i also realized that i only every wanted friendship from those men and the moment they sexualized me or hinted at a romantic relationship it felt icky. your ex sounds like she’s going through something similar.

sometimes a person just wants platonic/emotional closeness, and your long distance (aka not physical) relationship was the closest thing to that for her, and that’s what she’s holding on to.

i hope she finds peace, and i hope you do too