Bex, you hit the nail on the head with trying too many things. Thats why I think it is good to go back to basics and start rebuilding one's diet with 1 food at a time to see what works and what does not. That way you can eliminate the offending foods 'cause you are building from a solid base.

Tea is not a good idea, the bags and tea itself are very moldy. Tea of course is a diuretic which takes moisture out of the body. Of course you don't want to put any caffeine in the body at all. After rebuilding your diet and strengthening the intestinal system if you want a cup of non-caffeinated tea I don't think it would be a major problem.

Very hot or very cold foods irritate the intesintal system. Room temperature foods are best, warm or chilled are fine.

Personally all I drink is purified, room temperature water as I've gotten used to it and come to enjoy its simplicity.