There may be an underlying medical condition at play here.
Depression is known to be a mood killer - and depression does not always mean that one is sad all the time.
Low Testosterone levels can lead to a lack of interest in sex...
Stress, Diabetes... Well there is probably a long list there somewhere.
Then there is a little known sexual dysfunction called sexual anorexia:
http://en.wikipedia.org/wiki/Sexual_anorexia
From what you have written, I lean toward that as being the underlying cause.
Quote:SEX DOESN'T THRILL ME AT ALL!!!!!!
Sex doesn't thrill you, but are you able to do the mechanics (get hard, reach climax, ejaculate)? If so then this most likely is not an organic/biological issue - it is most likely mental/emotional.
Quote:I now find it difficult to look at other guys or even be touched by them
You came out pretty late in life, then you tried a (one) relationship where clearly that individual decided to rip your heart out, throw it to the ground and jump up and down on it. I suspect that 'bad experience' drove you down the road of sexual anorexia. The sentence above is revealing on how you are approaching intimacy/relationships (not just sex).
Go to a few sites that discuss Sexual Anorexia and get a more complete list of symptoms and read a few 'stories' of others and see if this fits more with you.
https://www.google.com/#psj=1&q=sexual+anorexia is a good start.
Either way, this is undoubtedly a subject you should bring up with your doctor. At least get tested for the medical/biological potential issues that could exist here. Diabetes and Low T are serious enough on their own.