Because God has promised that he will never give you a commandment that you do not have the capacity to obey, you can rest assured that the one and only reason for your disobedience is a lack of desire.
We are given everything necessary to become saved. If we fail in the task after having been correctly instructed in the gospel, it can only be for lack of desire.
27 Wherefore, men are free according to the flesh; and all things are given them which are expedient unto man. And they are free to choose liberty and eternal life, through the great Mediator of all men, or to choose captivity and death, according to the captivity and power of the devil; for he seeketh that all men might be miserable like unto himself.
28 And now, my sons, I would that ye should look to the great Mediator, and hearken unto his great commandments; and be faithful unto his words, and choose eternal life, according to the will of his Holy Spirit;
29 And not choose eternal death, according to the will of the flesh and the evil which is therein, which giveth the spirit of the devil power to captivate, to bring you down to hell, that he may reign over you in his own kingdom. (2 Nephi 2:27-29)
Most Christians do not actually desire to obey God. They are interested in obeying God, but they allow their desire for other things to dictate their sinful behavior. Desire isn’t the same as interest!
Most people get caught up in Jesus’ godliness: the gospels are full of supernatural qualities. These qualities are wonderful, but they should not take away from his humanity. We can learn as much from Jesus’ humanity as we can his godliness. Jesus is our Lord, Savior, and the son of God. He had incredible godly power to work miracles, and even had power given him over his own life. However, while on the earth he did not have a superhuman power against sin. He was subject to all temptations of the flesh—in fact greater temptations than any other man. Yet, he was sinless. His sinlessness was not a manifestation of God, but a manifestation of righteous desire. No man will atone for the sins of the world. No man will resurrect himself. But all men can—and must—exercise the same desire to do God’s will as Jesus possessed if they will be saved.
In this world, we can either choose good or evil. Those who choose good will be saved. Those who choose evil will not.
11 Now, concerning the state of the soul between death and the resurrection—Behold, it has been made known unto me by an angel, that the spirits of all men, as soon as they are departed from this mortal body, yea, the spirits of all men, whether they be good or evil, are taken home to that God who gave them life.
12 And then shall it come to pass, that the spirits of those who are righteous are received into a state of happiness, which is called paradise, a state of rest, a state of peace, where they shall rest from all their troubles and from all care, and sorrow.
13 And then shall it come to pass, that the spirits of the wicked, yea, who are evil—for behold, they have no part nor portion of the Spirit of the Lord; for behold, _they chose evil works rather than good_ ; therefore the spirit of the devil did enter into them, and take possession of their house—and these shall be cast out into outer darkness; there shall be weeping, and wailing, and gnashing of teeth, and this _because of their own iniquity_ , being led captive by the will of the devil.
14 Now this is the state of the souls of the wicked, yea, in darkness, and a state of awful, fearful looking for the fiery indignation of the wrath of God upon them; thus they remain in this state, as well as the righteous in paradise, until the time of their resurrection. (Alma 40)
You must choose to follow God in each choice, every time. You must deny yourself of all ungodliness, and every wordly lust, and keep all his commandments.
Therefore, if a man bringeth forth good works he hearkeneth unto the voice of the good shepard, and he doth follow him; but whosoever bringeth forth evil works, the same becometh a child of the devil, for he hearkeneth unto his voice, and doth follow him. (Alma 5:41)
We are told plainly that if we love God, we will keep his commandments:
15 If ye love me, keep my commandments.
16 And I will pray the Father, and he shall give you another Comforter, that he may abide with you for ever;
21 He that hath my commandments, and keepeth them, he it is that loveth me: and he that loveth me shall be loved of my Father, and I will love him, and will manifest myself to him.
23 Jesus answered and said unto him, If a man love me, he will keep my words: and my Father will love him, and we will come unto him, and make our abode with him. (John 14:15, 16, 21, 23)
You cannot allow yourself to choose contrary to God’s will, even if it costs you your life.
And thus we see that, when these Lamanites were brought to believe and to know the truth, they were firm, and would suffer even unto death rather than commit sin... (Alma 24:19).
And they overcame him by the blood of the Lamb, and by the word of their testimony; and they loved not their lives unto the death. (Revelation 12:11)
34 ...Whosoever will come after me, let him deny himself, and take up his cross, and follow me.
35 For whosoever will save his life shall lose it; but whosoever shall lose his life for my sake and the gospel's, the same shall save it. (Mark 8:34-35)
The atonement isn't a magical thing: you really do have to change. The atonement isn’t a magic wand. It is a ladder, given to us by Christ, allowing us to climb out of the consequences of the fall. You really do have to be everything that Jesus is asking you to be. There is no other way. The idea of meeting God halfway is false doctrine.
You don’t keep the commandments because of slight discomfort. How can you inherit the same glory as one who kept the commandments even though it cost his or her life? While the sacrifice God asks is different for every person, the common element is that each recipient is willing to obey God in all things, in all circumstances, until the end of their lives.