I really do think your gums bleeding points at inflammation as a cause. What I guess each of us needs to figure out is what is causing the inflammation for us. I've known for years that wheat causes inflammation for me.
So far, things have continued to improve over the weekend. No new spots on my hands and the dots on my feet are fading. My elbows have continued to improve. I've been strict with staying gluten free. I think corn might also be a trigger for me, but I had a few tortilla chips on Friday without incident.
I'm going to keep updating as things change (or don't). I just hope this doesn't suddenly show up again in a week or something.
Another Update
I finally got the results from my blood test last Thursday and I saw my doctor on Friday. The blood was drawn when I still had GA on my elbows. It revealed that I had high liver enzymes (way high), high copper and also revealed some other concerning stuff. 
I don't know if or how that might be linked to the GA, but the GA is totally gone.
I had to have another blood test done to see if we get the same results. I'm hoping they are different/better now since the GA is gone and so is some significant stress. I started working out and my daughter is sleeping better, so I'm sleeping better. I guess I'll find out eventually... it took forever to get the results of the first blood test, so I really hope this one doesn't take as long.
nikki i am glad you got rid of it. i have ga for 9 months now. i have been told it will go away by itself but it keeps growing bigger. i have hashimoto's auto immunesyndrom and have never suffered from eating wheat but was encouraged by your post to start eating gluten free. my dermatologist says it is not an auto immune disease , but i will try nevertheless. is your ga gone for good?
So far, yes. I have no signs of GA at all right now. I really believe that this has to do with inflammation as the root cause.
I have had great result taking Hesh Karela & Neem Extract which you can buy online or health shops. I went to several dermatoligists and told there was no cure and given steroid based creams which I was not happy with. I went to an alternative health consultant who advised me to take a capsule in the morning and early evening, to avoid milk, chocolate, sugar, bread, spinage, lemon, oranges and grapefruit. I now only eat gluton free bread avoid sugar completely and also drink green tea. Whenever I forget to take capsules it flares up but once I take them again it vanishes. Its been incredible because I had it all over my arms top of legs hands and feet and it just kept spreading. The capsules of Karela and Neem have worked for me and I really didn't expect to have such brilliant results. I think its trial and error regarding what you can eat because I know that certain foods make it flare up eg anything tomatoe based, like ketchup or sauce, also milk. I have totally had to give up on chocolate and cakes but can get away with black chocolat in small amounts. Have substituted non salted cashew nuts for snacks and natural greek yogart with mango seems to be ok. I think everyone may be different so you just have to take note what makes it flare up.