Several factors involved—- the pumping stations lost power so water pressure fell to a trickle. Also homes in Texas are not insulated well-enough to withstand the extreme cold and prolonged lack of heating we experienced.
It was somewhat thermodynamics too— their house was a smaller 1-story house, ours was a larger 2-story house and retained heat long enough to weather the freeze before power came back.
Was super worried after the reports of water supply issues that the pressure would drop and the pipes would freeze while I was sleeping in my 41 degree house :/ Fortunately we are in the lower elevation zone so it never dropped more than a quarter or so(pressure or flow, couldn't tell).
It seems like you lost power around 8 hours and your house didn't lose as much heat as others