PA and Secretary Community - Deskdemon.com

I've been in my current role with a Fortune 500 company for 2-1/2 years - about 1-1/2 years ago, a woman in her late 20s joined the group.  We slowly became friends and she visited my house on a Saturday, my husband and I joined her at her birthday party.  There were red flags that I chose to ignore because she has interests that are more worldly than others in this office.  About a year ago she told me that she requires her friends to be very close otherwise she won't bother (red flag #1). at her birthday party, she ended up sleeping with a consultant in our group.  He went on with work but she became obsessive.  While I was preparing for an important meeting & had managers at my desk, she demanded a minute of my time, I walked around the corner and she told me "he sent me an email asking me to go to out, I'm going to tell him no, think that will get him?". At that point I turned around and walked back to my desk annoyed. About a month later, she told me that at a conference his manager asked her to have an affair.  I stopped hanging out and personal calls with her around that point and made our communications casual at work.  She had a birthday a few months back and I told a co-worker that we should do something nice (it was her 30th & she doesn't have many friends/family). He brought in donuts and we walked over to her office and said "Happy Birthday!" (making no mention of her age) and she went off on us about how people will ask her how old she is and how she won't get the projects she wants because of age discrimination (she's 10-15 years junior to the other managers). I have never witnessed this to be the case but stunned, I apologized and walked off.  My peer quietly told her she was over-reacting and we were attempting to be nice.  

Since then, she ignores me and if she is forced to ask for something, she will ask for it and under her breath give me a 'please'.  I walk by her in the stairwell and she won't say anything.  I've made a point to not play her games and will casually say hello just as I would anyone else.  

Since this event happened, I've learned that she has done this to others in the group and is close with her senior reports and people that she has to work with.  The dissed refer to it as being part of 'the club'.  Oddly enough, her office door opens directly facing my desk - since her birthday she often keeps it closed (good for me) but I've also gotten the sense that management has no idea that she is so socially undeveloped.  Any thoughts on how I can learn to not let this immature person (NOT a woman) get under my skin??

It's very difficult to give advice on how to stop people getting under your skin, because by default, the fact that you're posting shows that to a degree she already is.  

I've recently been through similar here, a whole office (one of our customers) chose to ignore me because I followed my boss's instructions and "offended" them (and it was a real humdinger of an issue!).  I felt very "put out" by the whole thing, and it did affect me.  I just kept telling myself act normally and they will need you before you need them, they will get bored of it before I stop finding it funny.  It's hard to believe but you need to keep yourself reassured.

I made a point of remaining my normal self and every morning when passing one of them made sure I called out "morning" etc.  Whilst they are speaking to me now, it's still very strained, but that's their problem, not mine.

The hardest thing to do is carry on as normal.  You are not the one being childish, you are not the one playing silly games.  She is therefore she has the problem.  I would try my hardest to remain polite and have that calm, rational exterior.

It sounds to me like she is extremely insecure about herself, needing all that "attention" and as you pointed out seems to have few friends/family.   I'd be tempted to chalk this one up to experience and let her get on with it.

I think you really nailed it with one phrase: socially undeveloped
This may be the only way she knows to interact and is just doing what comes naturally to her. It doesn't sound like she wants to intentionally hurt people, including you, but just doesn't understand how to interact with people and develop relationships.  That's tragic.

Try to look at it more from that perspective.  I don't think it sounds like she's immature, she never learned how to interact socially.  There had to be something good in her that made you want to initially become friends, try to remember what you saw in her then and just hold your head up high and be as normal as possible.

Thank you so much for the responses.  I will not let her odd personality have an affect on my job.  I work for a senior executive and cannot afford to be anything less than professional.  For some reason she tapped into my vulnerability but I will rise above it and anytime I am feeling weak, I will return to your responses to reaffirm that this is not about me.  I now feel fortunate that she has distanced herself!