Hmm...I have plenty of rue growing in my yard and only the Black Swallowtails use it. Can't think of any bug that would be eating it. Are you sure they're not first instar caterpillars? Perhaps you can get a photo to post that would help with the ID. I know those little critters are hard to see so hopefully there's a macro setting on the camera? If you're sure they're not cats then you can add some dish soap or detergent to a spray bottle of water and squirt it on your plants. Wait a few minutes then wash it off with a sprayer hose. If the bugs don't die then repeat it for a few more days making sure to wash the plants off real good. If you have caterpillars on it as well as the bugs then take some cuttings and set the caterpillars on them in the mean time. ~ Cat

I am so sorry this happened. You'll never forget about this chance meeting, will you? Some caterpillar stings are terribly painful and can cause severe reactions. Are you hypersensitive to other insect 'bodily fluids' such as those from ants, mosquitoes and the like? My own experience was with the Saddleback caterpillar. I thought that I had been shot when my arm brushed against the stinging hairs. The bad thing about the buckmoth caterpillar is that they are often found in numbers. So be watchful. Wear gloves. Keep some meat tenderizer with you when working outside. Make a paste of the granules to apply directly to the site right after you've been stung. It will help. Purchase some benadryl to keep on hand for such incidents, both oral and topical. I've seen people develop what looks like broken blood vessels where the spines entered the skin. Took several days for the whole thing to clear up and go away. Tell us how you are doing!

I know the second one as the Puss caterpillar, Megalopyge opercularis. I've heard that their sting is more painful than that from a Saddleback, which I am personally familiar with. Yikes! For insect cuteness, look at the Puss moth.....talk about cute and cuddly.

https://owlcation.com/stem/stinging-caterpillar-identification