I know exactly how you feel. There is just something about the daylight and the activity of people around you that makes it a lot easier to sleep. I've done some research on things like this, because even if I'm tired all day, as soon as the sun goes down I get intensely hyper (this is just a sort of person reflection:) and I found that people like me have a body clock issue that could do with childhood. When I was a small child, between 4-7 years old, I'd force my parents to keep a lamp on and the hallway light on while I slept. As well, I would then stay awake and play well into the night. Personally, because of my youth issue, I found it natural to sleep when I got tired, which happened to be when my parents would wake up to take me to daycare around 7am, and I'd sleep on the way there. Now, I find that sleeping in cars, in school, in the library, and anywhere where there is people awake is a lot easier. I also think it has to do with someone "watching over you" as you sleep.
Don't worry. Your life will get better. I spent an entire summer spending my days asleep and my nights internet surfing. I never work up in time to eat dinner with my family, and it'd be weeks between bathings. As soon as something to kick your butt comes in place--school, work, etc--you'll be forced to be awake during the day. I suggest having someone sign you up for at least a yoga, art, or cooking class during the day, maybe around noon, so you have to be awake by then.
When it comes to actually sleeping, well, you have to find your own system. I get extremely paranoid at night, especially since I have a very active imagination. If you have an animal, have it always sleep in your room. I find this takes the place of a person "watching over me" when I have my cat sleep with me. If you are petless, try a fan, a mp3 player, or your tv (which you seem to already use), to give you the allusion of activity. As well, I keep my thoughts shallow (maybe about what clothes I'm wearing the next day, what to eat for breakfast, what is on my to-do list) so I don't think too much. Just by running through a list helps keep my mind of scary subjects as well off of things that could stress me out or upset me. By staying shallow, I find it's easier to fall asleep.
The irony of this reply is that it's 4:00 am where I am, and I am unable to fall asleep.