It's weird, and kind of hard for me to answer. I wouldn't say it's just the internet, it's that a lot of my hobbies and things I enjoy are done on the computer as whole. Writing, roleplaying, graphics, HTML, drawing, voice acting, talking with a lot of my friends (our schedules prevent us from hanging out irl a lot), and etc.
There are times when I'm on here and I don't even feel like being online, but there's nothing else to do at times. I'm in a bit of a bind IRL, so if given the choice, when stuck at home I'd rather be on here than be alone playing a solo video game for hours, etc.
I guess I do have somewhat of an addiction to the computer as a whole, because it's something that I love doing, but like I said.. there's complications. XD