Also, you mentioned that you only eat GROUND flaxseeds because of your sensitive stomach. You should give whole flaxseeds a try, and if they do not hurt your stomach to keep trying it for a few weeks. People who have been cured by flaxseeds say that it does not work when they ground the flax seeds up too much, and only work when they are whole.
This has cured many people, so I'd try it one day and if the whole flax seeds do not hurt your stomach, give them a couple of weeks and see if your FBO goes away.
The apple + flax seed remedy is somewhere on this forum in the last couple of pages. This remedy worked for a lot it. Flaxseed oil works for some too.