Me either CF, I just wanted to make the point that a person may experience the same thermostat temp differently depending on the outside weather. My personal favorite temp range is anything in the 70s, get to 80 and it’s too hot for me. I have lots of friends who prefer temps in the 80s and 90s.
I think when you have your thermostat set at 68 and the temperature outside is in the negative temps, the temperature inside is less than 68 (or at least the temperature exactly where you are in the room is less than 68) because your heater isn’t keeping up. That’s not you being uncomfortable in 68 degree temperatures; it’s you being uncomfortable in <68 degree temperatures.