Hi,
As already mentioned, possibility of diabetes should be ruled out first.Other factors to be considered are :
1. Possible side effects of any medicines or sometimes, due to the effect of certain diuretic food items in the daily diet.
2. Urinary infections.
3. Prostate enlargement
4. Hyperactive bladder
5. High residual urine due to any bladder neck obstruction or thickening of bladder walls, or any neurologic reasons.
You could consult a urologist for diagnosis of prostate and bladder related problems. Here is an article related to prostate enlargement associated frequent urination symptom:
http://emedicine.medscape.com/article/437359-overview
Solace
Prizefighter is on to something. You certainly want to check into that. If it is diabetes, it is manageable and can totally live a regular lifestyle.
I was told it could be diabetes. I am not saying that is what it is, but you may want to be checked or you are just drinking a lot.