How does one fight insomnia ?

If you do have sleep apnea it is harder to figh insomnia.
Insomnia can also be caused by chemical imbalances of your serotonin, your adrenaline and so forth.

Sounds like you really should be checking in to a sleep clinic if you are waking up suddenly through the night too.

What sort of insomnia is it? Do you have trouble getting to sleep, or staying asleep once you've dropped off?