Simple, he can't. "Neither is the woman without the man nor the man without the woman in the Lord." We are both to be worthy in order to live eternally with our Heavenly Father in the Celestial Kingdom. We are all promised that if we are faithful to our covenants, keep the commandments, believe in Jesus Christ that all the blessings of the kingdom can be ours. I do not know the specifics of how that will be done, but I do believe that those worthy to live in the Celestial Kingdom will have that opportunity, and that they will have righteous spouses to continue their eternal progression together.