Hosea 1-4: Adultery Personified

Hosea lived during the reigns of Uzziah, Jothan, Ahaz, and Hezekiah in Israel.  God told him to take an adulterous wife to illustrate Israel's idolatry and adultery.  Adultery usually doesn't begin intentionally.  It starts with a glance, an innocent word, a second thought.  Then, gradually, it turns into something that ultimately destroys a marriage.  The two may live together, but their house is no longer a home, it becomes a prison of torment and strife.  Separation comes as the result of the pursuit of pleasure rather than the pursuit of the relationship.  There is no longer any faithfulness, any love, any acknowledgement of the commitment.  That's what played out in Israel's time. They toyed with the neighboring gods and fell in love with the fruit of the land, rather than the giver of the fruit, with disastrous results..

Hear the word of the LORD, you Israelites,
because the LORD has a charge to bring
against you who live in the land:
"There is no faithfulness, no love,
no acknowledgment of God in the land.
There is only cursing, lying and murder,
stealing and adultery;
they break all bounds,
and bloodshed follows bloodshed.
Because of this the land mourns,
and all who live in it waste away;
the beasts of the field and the birds of the air
and the fish of the sea are dying.
"But let no man bring a charge,
let no man accuse another,
for your people are like those
who bring charges against a priest.
You stumble day and night,
and the prophets stumble with you.
So I will destroy your mother-
my people are destroyed from lack of knowledge.
"Because you have rejected knowledge,
I also reject you as my priests;
because you have ignored the law of your God,
I also will ignore your children. - Hosea 4:1-6 NIV

Just as Hosea took back his unfaithful wife, God, who promised to drive out the adulturous Israel, also gave the promise that one day, Israel would seek the Lord and would be united in a bond that could not be broken.
 
I will betroth you to me forever;
I will betroth you in righteousness and justice,
in love and compassion.
I will betroth you in faithfulness,
and you will acknowledge the LORD. - Hosea 2:19-20 NIV