I totally get where you're coming from. I'm not an ungrateful person either..but I have a hard time with crowds and especially with being in a room full of people that I don't know well on a personal level and having all the attention turned on me.
Last year, after having worked at a place for 11months, I was being laid off. The lay off came due to the person who's maternity leave I'd covered coming back for her job, nothing to do with my work performance. Anyways, the whole office threw a going away party for me. Even though I knew that they liked me, I got along with them on a "work" friendly level, I was completely and totally uncomfortable. I sucked it up, pasted on a happy face, and went into the boardroom to get it over with..While I appreciated the thoughtfullness I was totally wishing I was somewhere else because I was so nervous and out of my element that I wanted to crawl somewhere and hide. I did get through it, and so will you...just know that you're not the only one who feels this way about having the attention turned all on you, especially at work.