kishore, with great respect to you mate, your letter on here should have been posted in the post office mail for the attention of Mr. Humphrey Smith, and sent to the brewery, and not on this site.
We only presume that he looks at this site, and therefore posting on here may not get his attention.
I personally would be most annoyed by any manager/manageress who did not welcome a customer of any colour or creed who was able to pay for his/her drinks and be a responsible drinker.
If things don't improve and you are absolutely sure that you are being edged out of the pub due to your colour or beliefs, and its not just your "gut feeling", then contact the brewery. I sincerely hope that you are wrong about this and that the management couple make you welcome in future.