I go to bed at ten and I am still awake at midnight. I can not seem to switch off.

It sounds like you could be producing a lot of stress chemicals during the day, which are then making it hard for you to switch off. 

I would suggest taking A.Vogel AvenaCalm, one dose in the morning and one in the late afternoon/early evening. Then take our Dormeasan Valerian & Hops drops in a little water, 30 minutes before you go to bed.

You could also take a magnesium powder at night, and a B vitamin Complex is always a good idea if you are under a lot of stress (ask in your local health food shop). 

I would try to not drink caffeine after noon, and make sure you are not eating too late at night as well.

If this does not help, let me know, but I am sure it will.