Felicia, sounds like you got a great Christmas gift last year! Sorry about the pests! When you give them supplemental lighting indoors, the bugs thrive.

I wouldn't cut anything off just yet. It's not unusual for them to bloom even after their leaves fall off. Hopefully removing the leaves and the lights will decrease your pest population, but take it outside and spray it down with neem once more before bringing it back in.

The bugs also like dry warm conditions. Misting a couple times a day annoys them. They also don't like circulating air, so a fan will help, too. I'm in zone 8b and when we have a stretch of warm days--70's or 80's--I take a bunch of my plumerias outside and leave them until the next cold snap so the hot sun and predatory insects help get rid of the pests.

Divine is a well-known water hog, so maybe give her a generous splash of water. Watering during winter is a problem for newly-rooted plumeria, and those that have shut down on their own and are sitting in wet cold soil for long periods, but I water many of mine during winter and they do fine. You just have to keep an eye on each individual plant and see how it's doing.

Good luck!

Thank you jandey. I am also in 8b. Yes, the divine was a Christmas gift from last year. :) Thank you for the advice!