Lifting you up, my friend. Like Song_of_Storms said, you are not worthless. In the times you're tempted to think that, think about what Psalm 139:13-16 says (divinity capitalized):
For You created my inmost being;
You knit me together in my mother's womb.
I praise You because I am fearfully and wonderfully made;
Your works are wonderful,
I know that full well.
My frame was not hidden from You
when I was made in the secret place.
When I was woven together in the depths of the earth,
Your eyes saw my unformed body.
All the days ordained for me
were written in Your book
before one of them came to be.
As far as not making friends... well, if I can say this the way I mean it... Information Technology people are often a strange bunch. (I work in IT at my job I've dealt with plenty of other IT people, so I can say it.
) Some of them can be really nice, then turn around and be some of the biggest jerks. My guess is that you're experiencing some of that.
My advice: Try not to be like that. Instead, take a positive attitude as much as you can. Don't be the one who always speaks a negative word in the office, but be the one who encourages. I can't promise it will always be accepted, but I think you'll find your own outlook is different. Also, show yourself to be friendly. I know that can be more difficult when you're shy, but you might just make some friends that way. And if you've done all you can to be friendly and they don't accept it, they're probably not the kind of person you want for a friend anyway.
I'd also be cautious about allowing myself to be too "unbusy," especially in this economy. If you find yourself with nothing to do, seek tasks on the job that you can do. If you can't find anything, seek training and educational resources offered by your employer. It should show your bosses that you appreciate having your job and want to do the best job you can. Is it kissing up? Yeah, sort of. But in this economy especially, it may help you out in the long run.
Anyway, hopefully this is of some encouragement. I'll be lifting you up in prayer.