Insomnia! What to do?

Dear friends, I have had insomnia for many years. I am 53 year old male in good health with no outstanding worries and life is good for me. I am presently taking ativan 1-2 mg at night for sleep.Sometimes I can fall asleep butcant stay asleep and then sometime its the opposite. I wake up many times a night and not to go to the bathroom although sometimes I do. Mainly because I feel since I am awake I might as well go. My prostate is fine. I have tried meltonin, valerian root, kava kava, passion flower, and so on. These supplements keep me awake. I know that the ativan has proable damaged my circadian rhythm but it is the only thing that helps me sleep. I would like to get off ativan because I know it is not good for me having taken it for approx. 15 years. This is going to be a tought nut to crack but I just know that you good people that respond on this site are blessed by the hand of God and will suggest something for me to try that will change my condition. Give me your best shot. I know you will. Thanks.