And here in Puerto Rico. I could have written most of your post! Same experience with eggplants—finally pulled them out. Peppers, ditto. Neem, Sevin, wash with insecticidal soap, NADA. I used to garden year-round with the same plants you grew, but in the past couple of years, the whiteflies became my garden’s bubonic plague. I tried companion planting—no luck. I planted a variety of oregano —recommended by a friend. NADA (but lots of oregano!). To save my peppers I finally succumbed to malathion—organic for decades, now I use poison! It worked and I saved the remaining plants, but after harvesting and scrubbing them, I pulled them. I have stopped gardening for the present. (I also had cucumbers, squash, and kale turned into confetti by bugs.) I am inclined to believe that the bugs did develop immunity to insecticides.