Long Time Since We Did This, Huh?

Dear Cordelia:
I have an acquaintance that I a) have to have contact with on a regular basis, and b) am obligated to be, at the very least, polite to. She shares this obligation, but sadly ignores it fairly often, in a Bridget Jones Jellyfishy sort of way. I can think of a number of reasons why she may not like me very much, but frankly I don't think that excuses her bitchiness, since I've never been anything but nice to her. When confronted with said acts of sneaky (or not-so-sneaky; pretending I don't exist while I'm talking to her isn't exactly subtle) mean behavior, she says she never does anything of the sort--and, to be fair, she'll be friendlier for a while, but then it'll all start up again. What should I do?

Cordelia says:
Well, it doesn't seem like asking her to stop does any good. If she refuses to admit to (or genuinely doesn't recognize) her bitchy behavior, it's unlikely she'll start doing anything differently. But I have to ask, why do you care? I get that it's difficult to be around someone who is mean to you, but getting your feelings hurt over it is silly. I'm guessing that the "reasons" you mentioned include jealousy, as is often the case, and there's really no getting around that--instead, try to view her behavior as a kind of backwards compliment. Also--quit being nice. You can be cordial, but don't be nice. It'll only make you resentful, and it'll only piss her off. Which could be fun, but probably wouldn't help the situation much in the long run.