it is very sad... i am sorry this has happened... but please try not to blame yourself, honestly. you sound like a really good plant-mommy.

You know, had you brought them in, when it was already pretty cold out, because of the expected severe weather, some might have suffered and even died from shock... because indoors is always much warmer, especially nights, and usually the humidity differs too.

We have more of a seasonal change here, and my mom does bring plants in, but she has to do so when it is still not very cold out... sometimes it has gotten cold too suddenly and then it is too late. you could not have foreseen how cold it got and the necessity to bring them in. also some plants don't take kindly to being moved, period and you just never know how they will react to that stress.

like others have said, some may still have healthy roots - cutting the plant back is good if the foliage is dead. my mom usually cuts back into the wood progressively until she sees lymph inside (green or white... not hollow or brown).

oh... should you end up with a sudden cold emergency like this again - you might try buying a large see-through plastic tarp, and cover your outdoor plants with it. it will protect them to a large degree but they won't undergo the shock of moving indoors.

i hope many of the plants recover for you.

(((HUGS)))

~ waves ~