I have found that taking "anything" consistantly to help you fall asleep over a period of time becomes a habit. When you stop taking it there is a relapse of insomnia. Depending on what you were taking as to how much of the new insomnia is psychological or physiological. Either way to sleep naturally again will involve retraining the mind and the body. I've been on both sides of this coin, and the things that correct sleep patterns for me is to get up at the same time every day, whether you slept an hour or ten hours get up anyway at the same time. Get some exercise during the day and avoid stimulus around when bedtime should be. If you are capable of naturally going to sleep then you will after a few short nights.

This has worked for me sometimes, and other time after a few nights of 1-3 hours sleep I go back to taking something for sleep.

Benedryl is a good litmus test. It will make you sleepy and help you go to sleep, however you will wake up as soon as it wears off if you still have a serious insomnia. If you don't wake up till several hours pass and get some rest then yahoo. This is just what has worked and not worked for me, your mileage may vary.