Re: Annoying problem.
I often know I need to have a bowel movement because I start to feel nauseous. However, unlike you, I do tend to go daily or at least every other day (depends on my diet).
I'd double check, if I were you, that you are indeed getting the fiber you need. If you are, then I'd start looking for things that can cause constipation. For me, prescription painkillers will constipate me (like Vicodin), but one of the worst ones for me are calcium supplements. I always thought it was the calcium itself, but my doctor says it's actually the binders they use and that if you want to take a calcium supplement you should take a liquid one.
I don't know if any of that pertains to what you are going through, but I hope you find some answers here.