Tough call considering 62 years old, worsening conditions and possibility of getting hit by a car in the darkness. It really depends on the exact circumstances. I assume she did have gas to keep the engine and heater running? Was it one mile level and direct or up and down with lots of intersections, etc. I am not infirm nor slowed by my age all that much and have had situations in the mountains where I wasn't going to be covering 100 feet, much less 5,280. And I am a skier and off-roader.
Just an FYI. The gas lines were the same as Sandy on Thursday into Thursday night.
When I went into work Friday, all the stations I passed were out of gas.
If she had got out of the car and been killed by a snowplow everyone would be saying “See, she should have stayed in the nice, warm car and waited for rescue”. I remember how close I came to getting hit just changing a tire on the shoulder of an interstate once (yes, in a snowstorm).
This is Long Island—it is dullingly flat.