Hi, Lori. I'd second the advice about taking a break from leading, if it's really getting to you. Of course, simply saying "no" a lot more frequently has the same effect, if you're not really wanting to give it up completely.

I hit the same burnout point a few years ago; I took a year or so away from it, and then eased back in. I found two local folks (an outfitter store, and an independent guide) who run trips (mostly beginner, but a few intermediate) for a fee. I end up paying to go along (though they occasionally give me a discount), and I function as an unofficial "assistant leader." They make all the decisions and deal with all the problems, and I get to do the stuff I like: work with the folks who do want to learn. Occasionally, I'm able to help turn a borderline idiot around, but if I don't want to deal with them, I don't have to.

If you do want a vacation, take one. If you're like me, you started doing this for fun, not as a job; when it quits being fun, I'll stop. Luckily, I'm nowhere near that point yet.

Finally, remember what Kevin Costner said in "The Guardian": "you swim as hard as you can, for as long as you can, and save as many as you can; the ocean takes the rest."