We're free to divorce if our spouse commits adultery.
(Matthew 5:32 NIV) But I tell you that anyone who divorces his wife, except for marital unfaithfulness, causes her to become an adulteress, and anyone who marries the divorced woman commits adultery.
If, however, it is not God's initial plan for marriage, God created marriage for life but some took this word to excuse sin and thus give freedom to the desires of the flesh and that is where we should be wise. and understood