Hi,
Same thing happens to me. I wake up around 2 or 3 then every hour and a half (like every REM cycle)
I used to keep the TV on, until my therapist told me that what I was listening subconsciously kept my brain active and thus awake. She suggested white noise, or meditation music. It made a difference. Lately I've been reading before going to bed. I think this is why I'm having a hard time staying asleep. Even with Ambien I have a hard time falling and staying asleep.