You have your internal clock messed up. If you want to go to sleep earlier, try getting up an hour earlier every day until you are up at the time of day you want to be awake. By getting up an hour earlier you should be tired an hour earlier as well, so will go to sleep earlier :)
I have the same problem and I have found that a good natural way to help you sleep is with melatonin which is a natural hormone your body creates but we (people who can't sleep) have less of that hormone so we have difficulty sleeping. you can pick some up and almost any drug store, try small doses first, and if that doesn't help then move up in milligrams.