Do you have any pets? Animals can be really effective in alleviating loneliness. I'd say it's like having a roommate minus all the compromises (thermostats, garbage, dish washing, noise...)
It might also help to just spend more time outside your place. Even if it's just going to the diner or taking a fun class. You'll appreciate your alone time much more if you make attempts at being sociable. I don't know about you, but that's true for me. After a long day at school and work, all I want to do is shut myself in and just relax with my dog and some books.
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Here's to the crazy ones. The misfits. The rebels. The troublemakers. The round pegs in the square holes. The ones who see things differently.