I prefer being alone, but I need to be around others sometimes.
When I'm with friends, I enjoy being with them, but I find it exhausting because I'm always thinking, and guaging, and watching. I have to remember to ask questions (I get intent on listening, and I forget to start thinking of things to ask while the person is talking, instead of taking a long pause to absorb the information, think of what else I would like to know, and ask it), and I have to make sure I don't seem disinterested.
Sometimes I try too hard, and it's obvious. Then I get too loud, talk too much, and start pushing "activities," on people.
When people leave I'm never sure if it's because I've done something wrong, or if it's because they genuinely have someplace else to go. It's usually the latter, but I've had the former happen, and no one will ever say.
When people aren't around very often, or not part of my regular day, I forget to contact them. When I do remember them, I have to think of what to say before I start talking to them. The longer I go without contacting someone, the harder it is to do because I'm not sure what to say, or ask.
So, I enjoy the company of other people. I don't like being completely alone, but being with others requires a fair bit of effort on my part, so I don't to it terribly often even though I enjoy it most of the time. Sometimes, if there's too much social strain to the situation, I end up feeling down about it afterwards.
I also appreciate my alone time. I need a lot of it. I find it easy to keep myself occupied, and it's a lot less draining than being around others because I'm not worried about offending myself.