Yes, there is hope for crapemyrtles. Right now we are asking everyone to be patient and wait until spring and then take corrective action, if necessary, as the extent of the damage will be more noticeable then. Then you can prune back to live wood. If they have been killed all the way to the ground they will most likely come back from the crown of the plant, but wait until it is evident by new growth or the lack thereof. Other than that the best thing to do right now is keep them happy and healthy through proper watering and fertilizing as the new season begins to encourage vigorous growth to help them recover this growing season.