The line "Come on now, you're sleepin' on your feet like a horse" was not really in a "love scene" in the original story, it was Ennis showing natural affection to Jack as a friend who was being like a parent to Jack who was probably more than 8 inches shorter than Ennis.
Ennis. "Hell, that's the most I've spoke in a year." That line comes in the first evening after Ennis and Jack have traded places up on Brokeback Mountain. It was quite a while before they actually slept together in the tent, which happened well into the Summer of 1963.