I have trouble getting to sleep at night as well. My mind will not shut off. Not sure if it is anxiety induced or not. My doctor had me on 10 mg Ambien and my body got used to it and it became in affective. He has prescribed up to 2 mg of Ativan and taken me of the Ambien. So far, taking the full 2 mg will get me to sleep, but it sure takes a long time, 2 hours or more.
Not really sure what to suggest here, but I think you are already doing the right thing by talking with your doctor. Also, I have found that talking to your pharmacist is a very helpful way to understand which meds you can and cannot take (and it's free advice!).
that's a really low dose of Ativan and Ativan generally takes quite awhile to take effect, possibly an hour or two. I've tried trazodone too and that doesn't do much either - it's an antidepressant with sedation as a side effect, so they figure it will work but a lot of times it doesn't. If the trazodone doesn't work don't bother with it. You could combine the Ativan with Benadryl or Tylenol PM (although I'm no doctor, I've suffered insomnia enough too) but my suggestion would be to up the Ativan to, well, you could go all the way up to 2 mg if you had to, and take it an hour or so before you plan to go to sleep. :)
Good luck!