Hey, Nicks Nose - I hear you, I am also pre-diabetic and am treated for heart related issues including high triglycerides, high cholesterol, high LDL and low HDL. (And, I cannot tolerate statins to control these problems because they poisoned my muscles.) Combined with Irritable Bowel Syndrome (IBS), it's a double edged sword. Here's why:

Heart Disease recommendation: eat high fiber whole grains
IBS: can't tolerate whole grains due to cramps and other GI problems; there is a lot less drama in my digestive system when i eat . . . white bread

Heart Disease recommendation: eat healthy oils including nuts and olive oils
IBS: can't tolerate fats well, including healthy fats. must use oil sparingly. nuts are high in fiber and cause GI problems

Heart Disease recommendation: eat fresh fruit and veggies
IBS: fresh fruit is high in sugar (pre-diabetic problem) and fiber. to digest veggies without a problem, they are often best overcooked resulting in a loss of nutrients. raw foods? forget about them because they are difficult to digest and cause GI problems. tomato sauce? too acidic. corn? too much fiber resulting in cramping and more. used to love artichokes but . . . can't digest them properly.

Heart Disease recommendation: eat beans and legumes for fiber and protein
IBS: eat in strict moderation, preferably with a low fiber food like white rice.

In brief: I'm screwed!!!

Can't eat a lot of chocolate either - it's full of sugar and too calorie dense.