In my oponion both are really always loved.
I believe that the thing perpetual their love how in the beginning it's the separation almost constant during 20 years. It is the distance that gives force the love, one of the greatnesses of BBM.
How chameau said, it's enough watching the last meeting: Ennis goes tremendously jealous and Jack, when sees Ennis desperate and crying, quickly goes to console to him, Jack cannot see suffering her love .
Even when old Twist speaks about Jack's neighbor from Texas, Ennis containing tears, doesn't get upset, isn't bothered, even tries to smile: THAT WAS MY JACK!