Exaltation

"... and if you do this, behold I grant unto you eternal life, even if you should be slain."
Celestial marriage is essential to exaltation in the highest heaven
Lots of details about how sealing works.
Basically, being sealed to a spouse is essential for exaltation. It is also described as sufficient for exaltation, so long as one does not commit an unpardonable sin, here characterized as murder of an innocent (but not necessarily murder in the way that we normally think about it). Described that we will be made to suffer for our sins if we have been rebellious, but ultimately, will be exalted.
"That through the power and manifestation of the Spirit, while in the flesh, they may be able to bear his presence in the world of glory."
"The scriptures inform us that 'this is life eternal, that they might know thee the only true God, and Jesus Christ, whom thou hast sent.'"
"If any man does not know God, and inquires what kind of a being He is—if he will search diligently his own heart—if the declaration of Jesus and the apostles be true, he will realize that he has not eternal life; for there can be eternal life on no other principle."

Notes

The idea that people can become gods is often referred to as "theosis".

D&C 132 seems to proclaim a controversial idea that if we are sealed to a spouse, we will be exalted, because we went in through the gate, even if we later commit many sins, so long as they are not of the unpardonable variety. This is an unpopular idea, but it makes sense to me, as, if one spouse in a monogamous relationship could easily invalidate their own sealing, then it would seem that they could easily invalidate their spouse's sealing, seemingly putting their exaltation in jeopardy. Under such conditions, it would seem nearly impossible for anyone to be exalted unless most sealings to exaltable beings happened after their death by proxy. Our mortal sealings would then become almost meaningless. Of course, this means that many very disreputable people would seem to qualify for exaltation. Personally, since I hold that since we are our own judges, and since open and trusting interpersonal relationships characterize the celestial kingdom, the buffetings of Satan to which one becomes subject consist of an extended time of suffering that one undergoes to better one's self and earn back the trust of the exalted beings with whom we seek association. As Joseph Smith has taught, anyone who seeks to qualify for exaltation will have to demonstrate that they can remain true and faithful after considerable suffering, and those that fail such tests lightly will have to undergo them repeatedly before they are able to pass, after they have died, and before they resurrect. People often imagine that they would not like to spend eternity with their spouse. However, we cannot easily imagine what either we or our spouse would be like once we have qualified for exaltation.

I could easily be wrong in how I think about this, but such is the model I am working with at this time. One weakness is that it doesn't resolve what happens to a righteous person who was sealed to a spouse who did commit an unpardonable sin. I think it not nearly so troublesome to imagine that in rare circumstances, proxy sealings would be arranged to resolve the matter.

Cross-References