Sexless relationships

Wow. I just read several interesting articles and blogs regarding sexless relationships and the reasons for them (I won't bother going to into WHY I was reading these, but I'm sure you can guess...).

Stress and money problems seem to be considered reasonable causes of lack of interest in or desire for sex with a willing partner. I wonder, though (and the articles didn't say) if there isn't some sort of reasonable time limit on this (i.e., if after X period of time of lack of interest, it isn't enough to simply say, "I'm stressed" anymore and the problem might be greater than that).

Anyone care to weigh on this one? Anyone IN a sexless relationship? BTW - this is defined by the "experts" as a relationship where sex occurs 10 times a year or less.