Posted: 29/09/2016 at 10:23
Have they dried out? Chives and Parsley need regular watering, but Thyme prefers to be drier. When you say they could be dead do you mean the foliage has died down? In that case they probably are dead. Chives and Parsely will die down with frost, Parsley will come up in Spring and go to seed, it's a biennial. Chives are perennial and should come back every year, but will need re-potting and feeding.
When you cut them for use did you cut every single leaf? Maybe it was too much of a shock. Maybe they weren't hardened off properly.