Taking Charge of Your Fertility is a great book to buy if you're interested in learning about your cycle. I used the techniques suggested in the book both times Brad and I decided to get pregnant and it worked like a charm. Pregnant the first month both times. Maybe have been luck, too, but I won't discount the fact that I know exactly what day and time I got pregnant with both my kids, all because I read that book and tracked like it said to.
In regard to digestive health... have you read Primal Body Primal Mind? I know you commented on it on my journal so I think you probably have, but if not, check it out and read chapter 5 on digestion. From reading that and reading about all the attempts you're making at fixing your digestion, maybe the problem is low acid levels in your stomach. In Chapter 5 she mentions that if the stomach doesn't have a low enough pH (0.8 for digestion to progress) then H. pylori, a bacteria that's necessary for digestion but can easily get out of control, might have too high of numbers? Maybe review the chapter and see what she says about correcting that bacteria. Maybe that'll help? Idk... drawing at straws at this point b/c I hate to see you continue to struggle with this and want to see you get better.