I will say this, I've been struggling with depression for a few years now, and I have to say, the loneliest I have ever felt is when I make myself lonely. I live with three other people who aren't family, and I have to say there are still times when I feel alone in this house, in this small chunk of rock of ours, but I think the feeling of loneliness comes from not accepting who you are, I think loneliness comes from self-rejection. I'll go on mini-vacations between workdays and go to Japantown, or the Exploritorium in San Francisco or to the zoo in Oakland and while I'm there I don't feel lonely. It's perfectly possible to make yourself not lonely by having fun by yourself, just break the monotonous cycle of video games or internet, or whatever it is you are doing at the times you feel the loneliest and go out and do something.