My back is always tense. Its dufficult for me to sleep at night. I have tried heat/cold, muscle relaxers, massages, & ben gay, but no luck. Any suggestions?

Underlying causes. We presume that you have had a thorough medical evaluation to determine the cause of the muscle tension. If not, consider doing so. Back tension can be due to many things - underlying arthritis, degenerative disk disease, or muscle pull. Was there a recent or even distant injury? Are you on medications? Some can actually cause dystonia or muscle tension. Discontinuing them may help.? Work respite.
Stretch. I don't see the most important thing listed-- exercise and stretching. Consider yoga, or a similar program to improve flexibility. Stand, bend forward, and let your weight pull your arms toward the floor- gently do this multiple times per day, without bouncing. Take 15 minutes to stretch each am and each pm. It takes work, but works much better than any medication.