I think I could have hung on if I had been in love as much as Jack obviously was. This kind of soul-searing, life-changing love doesn't come around too often in the course of our time here on earth, and is extremely precious when found. It might be necessary to let go at some point, for some reason, but that decision would not be one to be taken lightly.
In fact, I don't know that I'll ever be able to let Ennis and Jack go. I have fallen hard for these two beautiful characters, and I may be looking at a lifetime colored by my complex feelings regarding them. Amazing, isn't it, that a story and film can do that to a person?
Scott