Great observations, Amanda, nakymaton, and everyone! It's amazing that after all these months, we're still uncovering new metaphors.
I can't add any brilliant animal symbols, but I do want to make a point about the push-pull thing and Lucise's good observation:
To add to this "push-pull" dynamic that the 2 men shared, one scene that always gets me - during the confrontation scene, when Ennis starts crying, Jack comes over to console him, he screams out "Get the fuck off me!", what does Jack do without even giving it a second thought or a moment's reflection? He grabs hold of Ennis, holds onto him tightly. Jack knew Ennis so well, he understood that Ennis was literally saying the opposite when he pushed Jack away, Ennis needed Jack more than he ever admitted, I think Jack understood this, although it was killing him that Ennis couldn't face this truth and accept it for himself..
This scene is a perfect bookend of the push-pull they go through at the very beginning of their (romantic) relationship, in TS1, right after they've lunged up from the bed. Ennis throws Jack off, but Jack doesn't back away. Then ultimately Ennis reaches out and holds Jack's head.
There's kind of a partial version of this in the fight scene on Brokeback. But that one, unfortunately, does not end in embrace.
These are all among the reminders that Jack can read Ennis really well. We wish that Ennis was more verbally forthcoming with Jack, at least we know that, despite Ennis' taciturnity, Jack gets it.