What to do about depression?

I am very depressed about my life and how i have lived it so far. I have been very solitary, i dont have alot of friends, i dont go and hang out with people alot, or go drinking, or anything to that degree. I am a semi-pro gamer, and that is how i hide from depression. I never have had a girlfriend, or made out or anything like that. Im not ugly to any degree, but ever since depression has hit i have let my body go. So how can i deal with depression?