Foul Taste and Smell in Mouth Every Morning for 3 Years

hi all, for the past 3 years I have woken up every morning with a foul taste and smell in my mouth and a sore stomach that hurts when I breathe. I have had candida treatments and stomach ulcer tests done, and so far, nothing has come from it. My doctor is convinced it is dry mouth, but I have never experienced my mouth feeling dry, and I am not a mouth breather. I had a rest done recently and I found my gut lining is pretty thin, bordering on leaky gut. However, I eat pretty healthy, lots of vegetables, leafy greens, high protien, low processed carbs etc. A few years ago I had a "mushroom cavity" and an abscess on my back molar and had to get it removed. during the healing process I developed a foul taste and smell on the stitching, and it hasn't gone away since. I also periodically have skin in my mouth blister and peel, leaving painful raw skin behind, making it painful to eat. I don't know how this all relates, but I am at my wits end, if anyone has any input whatsoever it would be greatly appreciated.