three years of post nasal drip

i was wondering if anybody could help me and throw some light upon this problem of very excessive and constant mucus in the back of my throat...

at the time when it started i was very run down. I remember that i had just had a cough that had lasted for one month and had kept me from sleeping... as the cough disappeared so i began to get a build up of phlegm and mucus in the back of my throat. Originating from approximately the position of my adenoids (adenoids) on the left hand side. Since then nothing much has changed.
For the first year or so it was very thick and i found it hugely affecting my confidence because the sucking sounds i had to keep making where quite disgusting. It seemed to me to be more severe than the usual case - in that drinking 2 litres a day of water etc certainly were not going to be enough to neutralise it. I went once to an ear nose throat specialist and they told me to try cutting certain things out of my diet etc... all of which i did and it seemed to make no difference..
on odd days the problem is better or worse though never absent and i cant see what affects it. It has been unchanged over 4 different living spaces - so i dont think it is a symptom of dust allergy.
I had a 10 week course of a nasal steroid and as that finished - which was approximately the same time as i recovered from mumps - i noticed that the condition improved - not quite half but almost of its former severity.
It was still very negatively affecting my everyday enjoyment of life. Then some time later one doctor prescribed me Atrovent Nasal - and this also seems to help - to the point that it is noticably improved from before - however it is still constantly there - and often i would rather be indoors than out because the problem is far more minor indoors -

and so basically i was wondering if anybody had any ideas that might be able to help me? Because od the time of its onset i wonder if it might be that the virus i had then causing the cough had somehow got lodged in my adenoids (adenoids) and was causing this - and how then i might unlodge it?
is adenoid surgery an option? how can i determine if the problem is the adenoids (adenoids)?
i tried some anti-histamines and they seemed to have no effect...

needless to say - any help would be greatly appreciated - ross