Bolivar is a Mexican cook who stays with the Hat Creek Cattle Company simply because "it was a good deal more relaxing than being a bandit" (1.85), proving that feeding a bunch of cowboys was actually less stressful than modern-day food service.
Bolivar's life in Lonesome Dove is comfortable. His life on the trail is not. After he accidentally wrecks the wagon, Bolivar quits, which makes him the only man to quit the trip. He considers returning to Mexico, where his "lovely daughters" (23.51) are, but he doesn't like his wife, so he doesn't.
When he leaves, he says he thinks he'll stop in Lonesome Dove and bang the dinner bell with a crowbar. It's his favorite activity, after all. Hey, you have to appreciate the small things, and maybe the small things are all Bolivar has, because when Call returns to Lonesome Dove at the very end of the book, there Bolivar still is, banging the dinner bell, even though there's no one to call. Now he can call Call, anyway.