I feel there is no better example that "Ol Brokeback got us good" than in the reunion scene.
It was post-Brokeback and 4 years had gone by. I think Jack was fully realizing the impact of Brokeback when he coined the phrase, while lying in bed, finally reunited with his love,and thinking of the reception he unexpectedly got from his normally reserved Ennis after he'd redlined it to Wyoming on hope and a prayer., It was that look on Jack's face as he was pushed back against the wall and practically devoured by Ennis as if he really could not stop himself if he wanted to. Jack said "4 yrs", and Ennis was like "yeah, 4 yrs." ...and still... it was Jack and Ennis, Ennis and Jack, like two peas in a pod.
Ennis was in the moment* long before Jack even got there and it showed, so pumped up with anticipation of seeing Jack again. There he was, sitting there waiting, beer after beer, smoke after smoke, hearing Alma speak about gettin a babysitter or something but not really hearing her words, the nervous jitter in his knee, not realizing his beer bottle was empty before he turned it up!, etc... , staring out the window, totally focused on Jack's arrival. ( excellent acting by Heath).. Jack was right, Ol Brokeback got em both good. MO.