I'm the kind of person who will be perfectly content whether I'm by myself or with other people, so that's a no. To be honest... most of the things that I enjoy doing the most, such as drawing, going online, listening to music, and reading, I prefer to do when I'm alone, so it's not a problem for me. I'm naturally a more quiet and laid-back person, anyway, so that's probably why I feel comfortable when I'm by myself.
That doesn't mean that I don't enjoy spending time with family and friends--I love to! Thankfully, we're all really close so I don't feel neglected or anything like that. The fact that my dog follows me around EVERYWHERE also makes it hard for me to feel lonely, lol. xD He's so sweet.