I Am 53 Years Old. As A Child I Was

I am 53 years old. As a child I was diagnosed with Thrush. Now, as an adult I still have that same bad breath and it is getting worse now. I sometime feel as though I am about to vomit. My grandchildren say my breath smells like "fart". Please help me. Gum problems I do not have. I do not drink nor smoke. Please help. Thanks