A lot of people with insomnia will spend an increasing amount of time trying to sleep. The problem is that remaining in bed while unable to sleep contributes worsening of insomnia. Art Spielman's 3P model shows how different combinations of predisposing, precipitating, and perpetuating factors contribute to insomnia.

Staying in bed leads to a conditioned association between bed and wakefulness with a corresponding decrease in bed being a discriminative stimulus for sleep. In fact, this association/conditioning problem is the target of stimulus control instructions for insomnia, which is a highly effective treatment for insomnia on its own, and when combined with sleep restriction, sleep hygiene, sleep education, and cognitive therapy. See the American Academy of Sleep Medicine Practice Parameters for a summary of the evidence.

The full set of stimulus control instruction for insomnia are:

1. Lie down to go to sleep only when you are sleepy.
2. Do not use your bed for anything except sleep; that is, do not read, watch television, eat, or worry in bed. Sexual activity is the only exception to this rule. On such occasions, the instructions are to be followed afterward, when you intend to go to sleep.
3. If you find yourself unable to fall asleep, get up and go into another room. Stay up as long as you wish and then return to the bedroom to sleep. Although we do not want you to watch the clock, we want you to get out of bed if you do not fall asleep immediately. Remember the goal is to associate your bed with falling asleep quickly! If you are in bed for more than about 10 minutes without falling asleep and have not gotten up, you are not following this instruction.
4. If you still cannot fall asleep, repeat step 3. Do this as often as is necessary throughout the night.
5. Set your alarm and get up at the same time every morning irrespective of how much sleep you got during the night. This will help your body acquire a consistent sleep rhythm.
6. Do not nap during the day.

You can use these instructions on your own, or seek treatment from a psychologist who knows how to do cognitive behavioral therapy for insomnia (CBTI). There are many online such as online-therapy.com. You may also go ahead and try it on your own, but follow it closely and give it at least a few weeks to work. If you have had chronic insomnia for a long time, you can't just change the conditioning overnight. Have patience, find something pleasant to do when unable to sleep, and remember that not everybody needs 8 hours of sleep per night.