The Greek myth of  Eros and Psyche is an interesting one because there are so many moral lessons hidden in this tale. 
You can find one full version of the tale(there are variations) here, I'll just give a condensed version.

Eros was the Greek god of love, the Greek version of Cupid, but, while cupid is usually depicted as a baby or infant, Eros was depicted as a handsome young man and the son of Aphrodite, goddess of love.  Psyche was the beautiful daughter of a king.  So beautiful, Aphrodite became jealous of her.  
    So Aphrodite sent Eros to shoot one of his arrows into Psyche while she sleep, so she would then fall in love with the first creature she saw upon waking.  Unfortunately, when Eros was trying to scratch her with his arrow, he accidentally scratched himself and immediately fell in love with Psyche.  This made Aphrodite very angry and she told Eros to get out of her sight.  
    Unfortunately, since  Eros was completely in love with Psyche, he kept arguing with his mother about her treatment of Psyche.  Finally, Eros decided to boycott by refusing to use his arrows on anyone.  Since people were not falling in love anymore, no one was worshiping Aphrodite.   Eventually she gave in to her son and agreed to let him have Psyche.  
    So love returned to the world, but not to Psyche, so her parents went to the oracle for advice.  The oracle told them Psyche was not meant for mortal men, but for someone special.  She told them to take Psyche to a mountain and leave her there, which they did.  
    The west wind carried Psyche from the mountain to her new home.  The wind dropped her at a castle that seemed to be unoccupied.  Invisible servants fed her.  Than, after a bath, she was led to her room.  After a while she heard a voice in the room with her.  She could not see Eros, but she could feel him.  The young god made her very happy, for awhile.  Psyche kept asking Eros when she could see him and he kept replying "soon", but it never happened.  
    She also complained that he was gone during the day and she got lonely.   So Eros brought her sisters to her for company.  Unfortunately, that was a mistake.  The sisters started asking questions about Psyche's husband and, when she told them that she could not actually see him, the sisters insisted she must be married to a monster since a handsome man would want to be seen.
    After the sisters left, Psyche began to wonder why she could not see her husband and why he went away every day.  She imagined that maybe he had other brides in other castles that he visited during the day.  So, late at night. after Eros was asleep, she carried a lamp into his room so she could see who she had married.  When she saw that it was Eros, handsomest of the young gods, she leaned over and kissed him.  He woke, and when he saw Psyche with the lamp he became angry and left her.  She cried, and begged him to come back, but he would not.  Eventually though, Eros got Zeus to make Psyche immortal and they could then marry as gods and be together eternally.

It is said that this story is the basis for the fairy tale "Beauty and the Beast" although Eros was not a beast.

    As already mentioned, this tale is full of moral lessons, some obvious, some more subtle.
The more obvious ones include:

• Jealousy doesn't get us what we want.
• When we make an agreement, we must stick to it.
• Just because somebody loves you, doesn't mean you can't drive him/her away with jealousy or mistrust.
• Don't let others talk you into something you know is wrong.

Less obvious ones are indicated by who we're dealing with here.  Eros, god of love.  Psyche is a name which means both butterfly and soul.   So the trials and tribulations of Psyche represent the human soul which is purified by suffering until pure enough to be in heaven and experiance eternal love.