Niecie,
You know, when I am reading your posts I get the feeling that, yes, it is his illness that is the root but.....there's more to it.

I have this sense that his erection difficulties are causing more of a problem than the actual stomachache, especially in light of the fact that he is able to ride motorcycles, clean a pool, maintain the lawn and a high stress job. It just doesn't add up, you know?

But what really stands out is the quality of sex going down. It appears that he is becoming so worried about staying hard that he is making that (and consequently his orgasm) the goal, instead of keeping in mind that YOU are there also.

It sucks to be him these days, that's for sure! I feel very sympathetic to him..I think he has a few big issues to work through. The first being, How is he going to handle occasional impotence for the rest of his (and his wife's) life? And secondly, How is he going to handle incorporating a sex life into a life filled with a chronic stomachache.
It can be done, N.
If he is able to do those other things mentioned above, then he will find a way to accomplish this, too.

Good luck!!

Honey