You just learn to accept that it is part of who you are. You have to let yourself know that it's OK.
Being frank about it, with the people around you, can make it easier. (for some, not all)
Accepting one's limitations is a good first step. Going beyond those limitations becomes a bonus.
I certainly can understand wanting to be more social at work, but it just not coming easy if at all. It's who you are, don't ever feel you need to apologize for it.
I was somewhat able to be social at work. If it was a group going out for lunch, it was easier because then I could just fade into the background and let them talk amongst themselves. If you can go out to lunch as a group, that may be an 'in' to being more social with your cow orkers.
From time to time, there would be a group going out that wouldn't invite me. It felt insulting, but it really worked out best for me
I was in the unfortunate position of having to try and entertain vendors from time to time. Those were the longest lunch hours ever.
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Always do right. This will gratify some people and astonish the rest.