First of all she is a highly extroverted personality, I am likely more introverted, she's always seemed very happy to have me as a friend/colleague.
We worked together for around a year, I left briefly then returned and she was always saying oh I miss you, can't wait for you to come back, you're such a lovely person etc. And I felt valued by her.
We used to talk almost daily. I know it's natural that when you often leave jobs you don't stay in touch as much, I've had enough jobs to know how it is.
She used to send a lot of messages but I accepted it was just who she was, what I mean is that she could send 20 whatsapps in a row, like it could be slightly irritating but I was happy she wanted to talk to me a lot.
We used to talk a lot on Teams at work too. However things have changed and for some reason she will cut conversations off halfway through. Like she'll just stop replying.. I don't reply instantly most of the time nor do I expect anyone else to, but I'll have asked a question or whatever then 10 days later still no reply.
The other day I messaged on Teams just asking hi how are you. Ftr I can sometimes take a few hours to reply on Teams depending on how busy work is. She replied oh hi nice to hear from you bla bla, and then after 2 messages she said, sorry but im wayy too busy to talk to you right now with work so I'll talk to you soon.
That was 10 days ago. These things happen I guess, I'm feeling a bit fragile atm in general so it's not helping. However I guess it's annoying how she used to think it was ok to send 50 messages at once and now frequently just ignores me or tells me she's too busy. Best to just leave it really aren't I? I'm finding friendships can be quite transient.