@Geofram - also, please don't think I'm bashing your method. Since melatonin is not FDA regulated, there is no "set" way to take it. There are 2 important things to note - first, you are, actually, in a sense, cycling it by gradually reducing the dosage. This helps prevent your body from getting conditioned to stop creating melatonin on its own. Second, you found a method that works for you.
For Orathaic, if melatonin is not available to you, there are a few alternatives for you. I am recalling a lot of this from memory, so please double check this before taking it as fact. Look for a product called 5-HTP. It's a synthetic compound (in pill form) that your body converts into the amino acid Tryptophan (Tryptophan itself is illegal to purchase in the United States... don't know about Ireland, but if you can get it, research it first, I don't know much about it). At any rate, Tryptophan regulates your body's Seratonin output, and Seratonin in turn regulates your body's natural melatonin output (and has the added benefit of being a sort of 'happy pill'). If you can't buy Melatonin, it's unlikely that you'll be able to find 5-HTP or Tryptophan, but it's worth a shot.
If you can't find that, herbs should be readily available at most nutrition stores. Look for something called Valerian Root. Get a standardized form of it (it will list an active chemical on the label, instead of simply saying something like "Valerian Root - 500mg"). One capsule in the evening typically is very relaxing, although results may vary. 2 things to note - first, it's typically a big pill. Second, I've heard it described (not a lie) as smelling like "a filthy goat's ass". I personally would agree with that.
One final thing, orathaic - if you've had 6 years of problems, you may consider seeing a doctor. I am a bit of a hypocrite though, since I myself have had seasonal sleeping problems for about 12 or 13 years, and just treat the symptoms... and never been to a doctor about it.
Hope you find something that helps!