Matt answered...

The Lord would not command us to love each other so much during our lives only to tear us apart in the next life. We are one flesh just as the Lord is one with his church. The scriptures say that we are not to be put asunder.
Christ gave his apostles special revelations on this subject:
Matthew, Chapter 16:
Jesus said to his apostles:
19 And I will give unto thee the keys of the kingdom of heaven: and whatsoever thou shalt bind on earth shall be bound in heaven: and whatsoever thou shalt loose on earth shall be loosed in heaven.

What else would his apostles bind, and what else could the Savior mean, if not marriages? Christ put no limit on their binding power to bind relationships and covenants. Their power extends into heaven.
And he continued by saying:
20 Then charged he his disciples that they should tell no man that he was Jesus the Christ.
– because some things are kept sacred until later times when the world is ready to receive them.
Temple sealing and eternal marriage are primarily the subject of modern revelation through prophets in our time.

In the latter days, according to prophecy, Elijah has returned to join families together. Malachi 4:5-6. We believe that prophets in each age bring new revelation from God. Amos 3:7.
This latter day revelation has finally made clear how families are kept together in heaven—something people have wondered about throughout the ages. (Ephesians 5:32, wherein it says that the subject of marriage in Biblical times was “a great mystery”). In our time, the purpose of marriage and family is clear: ordinances are being performed to unite the whole human family throughout all dispensations of time. It is a unique work for the latter days. These modern revelations free human kind from the depressing, and divorce-promoting idea that the family becomes meaningless in the life hereafter. The Lord would not put us in a world so alien to our heavenly home. In heaven, families are the eternal organizational unit in his kingdom.