Oh no, not again!

Oh no, it's happening again. I feel like I'm losing another friend! Booo hooo hooo! This time it's a friend from work, which is harder to bear because I see them nearly everyday. When I said good-bye to her today, she just totally ignored me and drove off in her car. I felt like total crap when she did that. She's not as friendly to me as she used to be, and I really have no idea how it became like that. At the conference last year, she was giving me the cold shoulder too, and I was like "what?" And when I asked her about it at the time, she was like "Oh no no no, I'm just stressed! I wasn't talking to anyone". She's in a role now where she can find out about my nitty gritty details, and my skeleton might be my qualification.
I am proud of my qualification (and the title that went with it), but I have played it down so not to seem so big-headed. I have never ever liked the idea of big-noting myself. Even when I temped, I didn't crow on about how I was too good to do certain jobs. I just did 'em. The people there just seemed so nice that I didn't want to alienate anyone. Of course when a certain research officer came in, I found a comrade who I could talk to, about academia and the life of academics. She was the only person who I could actually talk about these things to. The officials seem to understand more than the admin.
Where I work, paranoia and jealousy seem to be rife, as are the politics. I stay out of these things where I can help it because it was just never my gig to begin with. I like my job, and the variety of things that i can do with it. But I'm getting side-tracked here...
Her best friend is a quiet one, and I have a feeling that she's never really warmed to me, and while she doesn't seem like the spiteful type, she has an influence. But losing a friend and knowing I've pissed off someone really painful. I just seem to be having this ongoing pain... I feel I can't talk to my closest friend at work about this because I have spoken about things like in the past and all I got was just the feeling that I was being paranoid and oversensitive... I really hope I don't go into depression.