I don't have loneliness specifically, but I have a tendency to "get stuck" on activities, and when I'm depressed, it gets much worse. Since I don't have the energy/enthusiasm/capacity for any good activities, I tend to do crappy mildly boring things for a long time, in order to stave off the more severe boredom of doing nothing. Sometimes the crappy mildly boring activities are social media (facebook, forums like this, funny picture websites). I remember once thinking, "I know I must be depressed because the internet has run out of captioned cat pictures I haven't seen yet!"