RV: Mobile Apocalypse

The weather changes across the whole planet, an extreme cold sets in, and some of the people caught in it mutate into zombies. In her first life she got through it on 100 tons of coal she had won in the lottery at her company's year-end party. A woman she had trusted sold her out and took her revenge, and she was killed in the cold. She wakes up on the day of the same year-end party, the day before it starts. This time she buys a run-down camper van and rebuilds it into a fortress on wheels, and she buys up military supplies and food in bulk before the cold arrives. Somewhere in the rebuild the van turns out to come with a system attached to it, and the system keeps her supplied. The temperature falls to minus 160 degrees. She drives out through the ruined cities and into the frozen country beyond, dealing with zombies and with mutants as they turn up. The woman who betrayed her the first time is still alive in this one, and so is a gang that calls itself the Midnight Circus, and both of them come after her.