I've NC'd for this.
I became friendly with someone last year, did the usual coffee/shopping/chat on phone thing, initially she was fun but over time started to demand more and more of my time and became moody and sulky if I had other commitments. She criticised my friends, told me to drop them, tried to get me interested in her interests and didn't like it when I didn't, hated it when I didn't agree with her etc. Things came to a head a few months ago. She was incredibly unpleasant and difficult when she saw me and was extremely rude to another friend of mine. I told her that I thought her attitude to my other friend was out of order but she wasn't having any of it. In fact she told me that I should be grateful to have her as a friend and listed many of my so-called faults that she was putting up with! I cut off contact. All ok except that since then she has sent all my dc birthday cards (all primary age) and I don't like it at all. Should I do anything? Or leave well alone and hope she forgets about it? I feel slightly unnerved, so please be gentle. She has form for becoming extremely obsessed with things.