The Savior said,

• "will ye not now return unto me, and repent of your sins, and be converted, that I may ^cheal you?" (3 Nephi 9:13)

 "The Greek word of which repentance is the English translation “denotes a change of mind, i.e., a fresh view about God, about oneself, and about the world” (Bible Dictionary, “Repentance,” 760). This means we are to change our thoughts and then behavior until we are turned away from our sins and are aligned with God’s commandments. This change of mind means that we are actually progressing toward what Paul called “the mind of Christ” (1 Cor. 2:16). Repentance is thus a continuing process in which each of us needs to draw on the Atonement for real relief, real forgiveness, and real progress." (See Article)

Jesus Christ made it possible for each of us to have real lasting happiness.  The Atonement means everything to me. I know that Jesus is our Savior.