Baby, it's warm outside

This winter has been tough on the bees. They have been flying all December instead of clustering and thereby consuming more of their valuable winter honey stores than if they were in cluster. I made them a 2 to 1 sugar syrup in November and put it in the top feeders, but it has all glazed over. The surface was covered with a sheetof crystallized sugar and they hadn't been able to get at it. I broke up the surface except on one which had crystallized almost entirely. and we'll see, but it's a major hassle making 2 to 1 in my cramped kitchen and getting it up to the roof, plus I don't understand why it crystallizes. Everybody recommends 2 to 1 and nobody mentions this problem.
I can only hope for seasonable weather or face a major death unless I can manage to nurse them through somehow.