I also don't have a positive blood test for celiac, but I've seen such a change in my bowel habits, etc, since going GF, I absolutely would not go back. Any time I watch someone eat something I know I can't, I just remind myself of all of the gas, cramps, bloating, and diarrhea, and I decide the doughnut or whatever just doesn't look THAT good.
Try to have a positive outlook for your GF diet. There are really a lot of things we can still eat, and all kinds of GF flours so that we can make up our own healthy versions of the gluten goodies.
Hugs,