Janet has been acting a little less than chipper lately, starting arguments and flying off the handle at the slightest sign of stress. Roger puts this down to "women's troubles," and thinks she should talk it over with one of her neighbors, like that nice Martha Simpson.
Like the other inhabitants of Vault 112, Rockwell is trapped in the Tranquility Lane simulation and subject to Stanislaus Braun's whims.
Tranquility Lane: Roger Rockwell is one of the residents you will have to kill if you choose to do all of Betty's tasks.
During the task Betty gives you to break-up him and Janet, you can either convince Janet into thinking Roger is having an affair with Martha Simpson. Or you can take Janet's rolling pin and kill Martha with and make Roger believe Janet killed Martha.
The name "Rockwell" may be a reference to the American artist "Norman Rockwell" who is known for his illustrations of Americana on the covers of Life magazine in the 40's through the 60's. Many consider his works to be referential of a simpler time, similar to the atmosphere of Tranquility Lane.