you have to stop obsessing about how you come across to others , the beauty of most workplaces is that they contain a mosaic of different types of people, loudmouths, grumpies, quieter,chatty, bulls******s, meanies ect ect just like life. you mix with people that appeal to you and make you feel comfortable, happier or relaxed, the grass isnt greener, being loud,mouthy or boistrous does not make you a popular guy with the girls, besides you will not attract the right type of girl.
like china says you are in a spiral of negativity, you have to start letting go of the constant psycho analysing, you are you and there is NOTHING wrong with that, maybe you need a better environment to work in? or different colleagues that make you feel happier to be at work.
my brother (age 25 very like you in attitude) moved jobs for the same reason, he works in a smaller place with nicer people and he has flourished so much that he has joined a gym and goes out occasionally with some work friends, no girlfriend yet but he has stopped beating himself up about the fact he hasnt got one, mind you there are more single people than attached these days