I do the SAME thing, and alot of it has to do with the fact that I am afraid that I won't wake up in time for work.
Here is my solution to build confidence:
1. Set your alarm and install the battery back-up...so if the power goes out during the night, you know it's still working.
2. Set your alarm on your cell phone
as an additional backup, about 15 minutes later than you normally get up....you'll be rushing, but you won't be late.
3. NEVER look at the clock when you wake up during the night...this creates anxiety and can make your insomnia worse.
4. Don't consume caffeine or sugar after 6:00.