I think it's called being "wendied" because there was a thread on here forever ago about a woman who had introduced a new friend to her friendship group, who had then spread lies about her and stolen her friends. The MNer who this first happened too named the woman "Wendy" (and I think she named the previous friends too), to explain who was who, and sadly for lovely Wendys everywhere, the name stuck.
I think years ago I might have been discribed as a 'Wendy' if an ex-friend had been on here, but from my point of view, I'd moved to a new area and made friends with a woman, but she was very intense. She introduced me to a group of her friends who were all lovely, but the inital friend's intense-ness was a bit much, so I distanced myself from her, which was helped by this coinsiding with end of maternity leave, and while we were both going back to work with reduced hours, her work pattern and mine didn't really fit for meet ups in the week anymore.
In the meantime, several of the friends she'd introduced me too were far easier to get along with/relaxed, and were either off work on the same days as me, or were now SAHMs, so I'd see them at toddler groups in the week, and sometimes I'd go for a coffee before/after a group with one or 2 of them. Original friend too umbridge to meet ups being arranged while she was at work, and would send snippy messages about being left out. This put the backs up of her friendship group.
I don't know if Original friend thought I stole her friends, or that I delibrately set up coffee/lunch meet ups on days she couldn't do. I was trying to make local friends who were around in the day when I was so I didn't get too lonely when DH was at work.
(I may well have meet these woman anyway, it's not that big a town!)