Coveting and Lusting are sins

 But one day, when he went into the house to do his work and none of the men of the house was there in the house, she caught him by his garment, saying, "Lie with me." But he left his garment in her hand and fled and got out of the house. And as soon as she saw that he had left his garment in her hand and had fled out of the house, she called to the men of her household and said to them, "See, he has brought among us a Hebrew to laugh at us. He came into me to lie with me, and I cried out with a loud voice. And as soon as he heard that I lifted up my voice and cried out, he left his garment beside me and fled and got out of the house." Then she laid up his garment by her until his master came home, and she told him the same story, saying, "The Hebrew servant, whom you have brought among us, came into me to laugh at me. But as soon as I lifted up my voice and cried, he left his garment beside me and fled out of the house."

Genesis 39:11-18 (ESV)

You would think Potiphar's wife had everything she needed or wanted, yet she chose to focus on what she could not have. She exemplifies an aspect of mental illness that is often ignored.
Coveting or lusting is a desire for something we do not or cannot have, and these desires eventually possess us until we act out in desperation. Coveting and lusting are similar in that they are both birthed from the desire to use something or someone for our personal pleasure. The misery comes because we were not created to find satisfaction in things but were created to love, not use, people.

Coveting focuses on how life would be if we had what someone else had. This could be a marriage, car, job, family, and more. The more we focus on what others have compared to what we have, the more dissatisfied we will be. (For some reason, we usually do not focus on people who have less than us and are content or happy.)

Lusting is the desire to use instead of love and destroy all semblance of respect, honor, and dignity.

Coveting and lusting are sins; those involved in a sinful lifestyle will be miserable. The answer is acknowledging our sin (1 John 1:9) and focusing on what is right.

Finally, brothers, whatever is true, whatever is honorable, whatever is just, whatever is pure, whatever is lovely, whatever is commendable, if there is any excellence, if there is anything worthy of praise, think about these things. What you have learned and received and heard and seen in me—practice these things, and the God of peace will be with you. Philippians 4:8-9 (ESV)