The source is Brokeback Mountain. Jack did not roll his own. He did not did not jerk off alone. This sentence was omitted in the French translation of the short story.
"sh*t no," said Jack, who had been riding more than bulls, not rolling his own. "You know that. Old Brokeback got us good and it sure ain't over. We got a work out what the f*ck we're goin a do now."