At first it almost seems as if nothing has changed between then and now - indeed they love each other as much as they did, but Ennis has become more deeply set in his matrix and Jack doesn't realize that he's never going to be able to dig him out. The "makin' a livin'" comment is the key, but because Ennis then goes off to the mountains with him, it doesn't sink in. they are happy for such a brief period in this scene.....