Some background: I'm fifteen years old, have but one friend, and never attend any parties or the like. I spend most of my time banging out code in front of my laptop.
Is it lonely? Certainly. Does it feel crushing, unbearably melancholy? Yes, it does. But I love it. You have so much time for productivity, so much time to do things you love, rather than having that time spent whilst pandering to the whims of others.
No girlfriend. No best friend. I tend to keep my distance. Ulcerative colitis doesn't help my cause much. But being social is something I see as a thing of my past. It's replaceable. Sporadic.
Learn to love loneliness. It's the only thing that will consistently love you back.