Yes, clearly Jack thinks breaking camp is no big deal, no signal to the end of their relationship, while Ennis does.
I experienced a similar sensation to Ennis's last week while taking down a tent that I had put up in the dark the night before. When I unfastened the cross beams the whole tent just deflated all at once and it was definitely a sinking sensation!!
I love the shape of the tent because it echoes that of the mountains so perfectly...