This is a post interpreting "Red River Shore."
Dylan has written many love songs. They include desire songs filled with urges, anguish songs marked by the sadness of the loss of a romantic partner, revenge songs that turn the anguish into fury, and love songs expressing mature feelings that mix desire, mutuality of attraction, and responsibility. The allegorical love song is another of Dylan's types. On the literal level, these songs are about Dylan's love for a woman. On the allegorical level, they are about Dylan's relationship with some aspect of God, represented by the woman. Such a metaphor goes back at least as far as the Biblical "Song of Songs" in which the male and female characters represent God and the Jewish people.
"Visions of Johanna" (1966) was the first of Dylan's allegorical love songs. In that song Dylan is with the earthly Louise while yearning for the spiritual Johanna. The exact nature of Johanna's Godliness is not clear in the song. She could be God as represented by a female, or a metaphor as in the "Song of Songs" tradition, or one aspect of God, or a private way that Dylan experiences God. There are also Christian interpretations of this relationship that I'm not qualified to offer. "Shelter From the Storm" (1974) is another extraordinary example of such an allegorical love song.
And now, joining this illustrious group, comes "Red River Shore," another song about the power of love. Dylan sings that the only woman he ever wanted was "the girl from the Red River shore." He couldn't convince her to be his wife, to stay with him permanently. The "girl" is not simply a romantic partner. Her spiritual nature is hinted at because others can't see her; when the singer asks about her, people "didn't know who I was talking about."
The memory of this hidden goddess sustains him. The rest of life feels strange. Her memory gives him songs but also sadness because he know he is now distant from her. One possible interpretation of this distance is that Dylan no longer feels as close to the aspect of God she represents as he once did.
Indeed, Dylan feels like he's dead. He invokes the hope that somebody can bring him back to life the way Jesus could resuscitate people. Dylan is very precise in his words. He alludes to Jesus using the words "guy" and "man," deliberately avoiding a Godly reference, an avoidance that indicates his separation from his born-again experience. Dylan is left believing only the "girl from the Red River shore" understood him and now she--his love on an earthly and spiritual plane--is gone. We are left only with the sad, haunting sounds of his longing for the life-giving love that is gone and will never return.