One thing nobody realizes about Marty Robbins 'El Paso', is that Felina never comes out when he's shot. Felina was a one time girl, who he had his one time with early in the song. During the song, the gunslinger is shot, and collapses on the road. He imagines Felina coming out to usher him out of this world, because it makes the dying process easier for him. The real Felina would've never even thought about the gunslinger after their liason because it didn't help her survive in her world.
The cowboy mythos is full of idealized love in the face of the banality of relationships and human behavior.