Q.large potted Gardenia plant
I bring my large, potted gardenia in for the winter, but over the last week, the entire plant seems to have died. The leaves became dry and the branches brittle. I cut the plant way back, taking off as much of the dead leaves and branches. What should I do now? Should I water it, or leave it dry? it gets 1/2 of sun in front of my sliding deck door. Should I fertilize it now? Trying to save the plant.

It is important that you maintain regular care for a Gardenia wintering indoors, as they do not go dormant. Gardenia are finicky and lack of humidity and indoor temperatures are some of the biggest issues for this plant.
Soil should be kept moist, but never soggy.
Check the branches, do the bend or snap and break off? Scratch the bark, it is green underneath?
https://www.gardeningknowhow.com/ornamental/trees/tgen/tree-scratch-test.htm
If you see signs of life, continue care as the articles below describe.
https://www.gardeningknowhow.com/ornamental/trees/tgen/tree-scratch-test.htm
https://www.gardeningknowhow.com/ornamental/flowers/gardenia/growing-gardenias-indoors.htm