I have a similar problem - I've been going to bed at 5-7am and waking up between 1-2pm. Something I found that helps is sleeping on the couch. It's a lot more uncomfortable than a bed and makes it that much easier to get up in the morning. I have yet to level out my sleeping pattern, but on nights/days where I need to get up early or don't want to sleep in, I sleep on the couch and usually have no problem getting up.

Also: SimplyNoise - The Best Free White Noise Generator on the Internet. might help you fall asleep faster if you keep using it and your body gets used to it.

Hope it helps, gl.