In Malichi 2 it says, "14You cry out, "Why has the LORD abandoned us?" I'll tell you why! Because the LORD witnessed the vows you and your wife made to each other on your wedding day when you were young. But you have been disloyal to her, though she remained your faithful companion, the wife of your marriage vows. 15Didn't the LORD make you one with your wife? In body and spirit you are his.[b] And what does he want? Godly children from your union. So guard yourself; remain loyal to the wife of your youth. 16"For I hate divorce!" says the LORD, the God of Israel. "It is as cruel as putting on a victim's bloodstained coat," says the LORD Almighty. "So guard yourself; always remain loyal to your wife."
God doesn't want divorce, but the husband is to treat his wife in a loyal and faithful way. God hates divorce because it impacts so many, especially children of the marriage. But there are other verses where it talks about how a father should love his wife and love his children. If the husband never repents, and never changes, then you have to wonder if he is a believer, which changes how things are looked at.
In Mark 10 it says, " 3"What did Moses say about divorce?" Jesus asked them.
4"Well, he permitted it," they replied. "He said a man merely has to write his wife an official letter of divorce and send her away."[a]5But Jesus responded, "He wrote those instructions only as a concession to your hard-hearted wickedness. 6But God's plan was seen from the beginning of creation, for `He made them male and female.'[b] 7`This explains why a man leaves his father and mother and is joined to his wife,[c] 8and the two are united into one.'[d] Since they are no longer two but one, 9let no one separate them, for God has joined them together."10Later, when he was alone with his disciples in the house, they brought up the subject again. 11He told them, "Whoever divorces his wife and marries someone else commits adultery against her. 12And if a woman divorces her husband and remarries, she commits adultery.""
Divorce was permitted in the old testament under Moses. Jesus said it was because man had a hard-heart. But he also said that it was not God's desire for people to divorce. In other words everything should be done for the marriage and not just give up. But in the case of abuse if does not mean the person has to stay and live with the abuser. 1 Corinthians 6, " 9Don't you know that those who do wrong will have no share in the Kingdom of God? Don't fool yourselves. Those who indulge in sexual sin, who are idol worshipers, adulterers, male prostitutes, homosexuals, 10thieves, greedy people, drunkards, abusers, and swindlers--none of these will have a share in the Kingdom of God." So as the Bible says, abusers will not have a part of his Kingdom, so it goes back to whether the person is a true Christian or not.
I think the key verses are in 1 Corinthians 7, "13And if a Christian woman has a husband who is an unbeliever, and he is willing to continue living with her, she must not leave him. 14For the Christian wife brings holiness to her marriage, and the Christian husband brings holiness to his marriage. Otherwise, your children would not have a godly influence, but now they are set apart for him. 15(But if the husband or wife who isn't a Christian insists on leaving, let them go. In such cases the Christian husband or wife is not required to stay with them, for God wants his children to live in peace.)"
Remember God hates divorce because of the effect on the children. But God also wants his children to libe in peace.
