Try taking your medicine for sleep at say 9pm every night no matter when you are going to bed. Also, you may want to be in the dark starting at about 11pm. If you get more consistent it may help.

If these things aren't helping than maybe you need to be taking something different.

I take trileptal at night. It is not a sleeping pill. It is an anticonvulsent like lamictal and also used for bipolar. It really helps me sleep. I take lamictal in the morning and trileptal at night.