Unfortunately, it's not just the temperature thing. A hive needs a good amount of bees in it to do lots of stuff, from tending to the brood and feeding the queen, to making wax for combs and guarding the hive. If there aren't enough bees, they colony is doomed.
However, you can take the queen and re-introduce her to another hive that may need a queen. Bummer about the hive though.