She's so flakey with friends. I don't know her personally, but I follow some people who know her, typical over sharers, and whilst they probably don't mean to air their dirty laundry on purpose, anyone with a brain can figure things out.
But basically, she's terrible with communication and will make friends very quickly, everything will be amazing, then either she'll go on holiday or gt a new bf and literally ghost them. To the point where people will publicly post stories asking for her to reply to a text or WhatsApp. Very similar to the situations with her boyfriends I guess, overnight love, then brutal dumping. All sounds very very toxic.