Skipy
There is nothing wrong with your voice it is very pleasant to listen to. The cow that told you you couldn't sing is just that.... A cow. She has the problem so don't make it your problem.
Sing in the choruses to start off with and get your confidence back again.
When YOU are ready try a solo amongst friends who are supportive and friendly.
Find what is called a "natural voice coach" they won't teach you an operatic style but will help you to maximise your own god given voice and with this will come confidence.
Confidence makes most people better singers.

I was told to "shut up and mime" when I was in a school play at 5 and I didn't sing until I was in further education and totally desparate to sing the marvellous songs I had discovered through folk. I was probably rubbish at first but improved with practice and am now fairly satisfied with what I have (voice wise) but still strive to improve all the time. You never really get over a hurtful comment like that but you can overcome it in time.
Love
Mary