One of the beauties of Creation, i.e. the universe as we know it, is the passionate attraction that occurs with certain couples. William Shakespeare wrote about it fetchingly in Romeo and Juliet, and ended it quite wisely. Had Romeo and Juliet married, it might not have lasted, and the beauty of their relationship might have ended, in its modern equivalent of divorce or unfaithfulness.
Theirs was a moment captured by time, like a sunset that lasts only four minutes, like a day lily that blooms only twenty-four hours. We can’t push Nature too far — it is beautiful as it is. Romeo and Juliet’s love was beautiful as it was; to demand that it last a lifetime is almost hoping for too much. Yet there are couples whose love lasts forever, as far as I can tell.
Yes, as quantum theory would lead me to believe, the adjective forever is possible. In this world, all things have an end; even the universe is predicted to die. But English and other languages have the word eternal. Don’t give up on that.