Jo, you've got tons of friends right here and I hope you realise that.
And yes, I think you have answered your own questions. I have a sneaky feeling that growth is something that's inate in us, which is one reason why we go a bit nuts when we are not following that path.
Boundaries will help, as will pointing the kids in the direction of organisations like al-ateen or local services that might help. Lighten your load a bit - you can't save everyone, especially if you are not "sharpening your own saw".
It will pass as long as you put some strategies in place to get some breathing space for yourself.
Good luck!