What's normal for a power bill difference between summer and winter on heat pump?

I live in the sandhills area and am trying to figure out if my heat pump experience is normal or if I'm an outlier. Last month's power bill was almost $300 but I spent only $160 in July.

With the recent cold weather it has been running almost continuously and as I'm sitting here the house is 5 degrees colder than it should be. I don't have gas or a wood fireplace to run, just electric.