R.R.
Have you tried melatonin? Our bodies produce it to help us go to sleep, sometimes if we have two much "blue light" activity from TV and electronics our bodies don't produce enough of it.
And have you tried eating something a little before bed that will help you to sleep? Foods that contain tryptophan, a sleep-promoting substance such as dairy foods, honey, bananas, nuts and seeds, and eggs are good. If you eat a carbohydrate-rich food along with something containing tryptophan it increases the effect, like cereal and milk, cheese and crackers, yogurt and crackers, or my fave, milk and crackers. Stay away from protein before bed, it's harder to digest and can keep you awake, as well as heavy high-fat or spicy foods for dinner, not good.
When cutting out caffeine make sure you stay away from tea, chocolate and even decaffeinated coffee, it still has caffeine, (found this out when my Dad had kidney failure and on the list of bad foods was his decaf coffee) at least 4 or 5 hours before bed, the same with any alcohol. Certain medications can keep you awake so check OTC and Rx drugs from pain relievers to weight loss pills to diuretics to see if there's any warnings of insomnia or that it can interfere with sleep. The same with smoking, if you do, it can keep some people up at night so that's a no-no in the evening. And stress. I think of things late at night and that sometimes keeps me awake (like tonight, my friend lost her husband yesterday morning and she and her young son are on my mind.)
Last but not least, is your bedroom comfy enough to sleep in? I HAVE to have a fan going, even in winter, I need the white noise.
Hope you can get to sleeping regularly soon, I know it's a pain not to be able to.