I had a weird thing. Small HCP patient facing team, part of a bigger department..
There was one young woman A, there who was always no more than civil to me. She seemed to get on with others, and was friends with one or two outside work. But did not get on with B, an older woman, like me, but who was a manager. B was often openly hostile to A in particular, and B didn't treat me that well, either!
Everyone else was absolutely fine towards me, including her out-of-work friends who also used to comment how different she was outside work compared to in work.
I wondered whether it was embarrassment? A had come to our bigger department on placement as a student, with other fellow students. 3 or 4 of her cohort joined us and they'd say how A was a bit odd, lasted 3 months in a shared house before retreating home, didn't really have any mates. But she was befriended by the older women in the department, where she became a bit of a pain, constantly phoning these women, asking if she could drop by (why they were making dinner, helping with DC homework etc), outstaying her welcome. I am friends with all these women.
But they recognised she was lonely so were nice to her.
Then, another woman joined the bigger department; she and A hit it off and became partners (now married). Suddenly, A froze out all the older women who had befriended her and whom she had been dependent on. Absolutely blanking them in the corridors. And A would know full well that I knew of this past dependency.
Then A joined our specialist team.
Anyway, we 'got on' as much as was professionally necessary- til B left. Then suddenly A was all smiles, all 'How was your weekend? How are your boys?' and sometimes voluntarily putting herself down to work with me, something we both avoided like the plague prior (and something I felt awkward about, given this volte face!).
Anyway, I (and the rest of the team) have no idea why B leaving caused A to thaw towards me!
I'm glad to say, A left us a year or so ago, though.
But people are weird.