I am a retired singing teacher and have done a great deal of stage work. However, my daughter forbids me to sing when her friends are around. At her birthday parties, she looks daggers at me if I join in with 'Happy Birthday' Consequently, I've become very self-conscious about singing and wish I could sing inconspicuously! I end up not singing at all. Your voice is such a huge part of you so don't be afraid to use it. (If you really wish you could do better, get yourself a few lessons; ANY one can sing!)