When I was a little girl of 6 or 7, I had heard my parents singing with Daddy on melody & Mother harmonizing. One day when we were all in the stationwagon riding through the Rockies, Daddy started singing a song, so I joined in with the harmony. I was immediately filled with awe--at the lovely sound! I had no thought of myself, but instead was convinced that when I was singing the harmony line with the melody a magical music fairy-or something like that-must have turned our combined voices into a special sound of beauty.
I still prefer to sing or play harmony. To me, being part of a Music ensemble is always more fun than singing or playing alone--onstage or off.
Some people are intimidated by harmony, therefore they put it down or or the person singing it. Few ever put down harmony which is instrumental, it's usually singing harmony which is more difficult. Dare to be different! Strive to learn more & get out of your rut!   
Become a better Musician and ask a fellow Musician to assist you. If you are really that intimidated by your talented fellows, ask a youngster to teach you the harmony part to a song. Most kids are terrific teachers because as a kid they are used to being corrected & learning new things, so they do not judge us as they teach us things. They also appreciate that a grown up respects them enough to ask them for help.
Instead of fussin' do somethin' to be a better Musician today!