Today I had an experience with the Lord and received the following:
I then asked the Lord about eternal marriage. When is this covenant secure? The Lord said that people may begin to feel the attachment to a spouse during their second estate, but not until the beginning of their 4th estate do they begin the process under a covenant that may endure. (Edit) For many it occurs for these fourth estate beings during the Millennium, but for some before. The Lord Himself performs the ordinance in the Garden created by the couple before they came to earth. It is very special and involves a sacred symbolic ordinance.
After this they are sealed and continue on together in the Everlasting Covenant moving from one estate to another, both condescending and resurrecting in glory until they become like the Eternal Father and Mother in their own dominion.