ANSWER: Before I tackle your question on spousal abuse, something must be said about divorce. In regard to divorce, Jesus stated that it is because of the hardness of people's hearts that God allowed divorce in the first place (Mark 10:2 - 12). God is looking for a commitment from people whom He has called to His way of life. We live in a throw-away world. The minute something does not work, it immediately gets tossed out when it could have perhaps been fixed. We should do all we possibly can to save a marriage before ending it. The effects of a broken home last for many years.
That said, in the case of spousal abuse, we must also consider that our bodies and minds are the temple of God. One should not remain in an abusive home if they can help it. Physical, mental or emotional mistreatment in any marriage is UNACCEPTABLE to our Father. If one is truly converted to him and His way of life, they will become his temple. He will live in them and walk among them in Spirit, be their God, and they will be His people.
The New Covenant, discussed in several different places in the Bible, is the agreement God offers man so that he can live forever. He looks at the temple of our hearts and minds and welcomes those who by their conscience have been keeping themselves separate (as much as possible) from sin and Satan the devil (the ruler and deceiver of this present evil world - Revelation 12:9). This separation includes honoring out spouse as our heavenly Father wants us to do.
Our Father commands us to be holy, pure, and not to defile ourselves with sin (2Corinthians 6:17, 1Corinthians 3:16 - 17). When a person is converted they are willing to keep a commitment to him and walk in His ways (Psalm 119:165, Proverbs 6:23). True Christians must put him first in their life (Deuteronomy 30:15 - 16).
In the New Testament Paul gives us several important principles and addresses the issue of how husbands and wives should treat each other in chapter 7 of 1Corinthians. Paul endorses peace and rejects any kind of spousal mistreatment.
13. And if a woman has an unbelieving husband, and he consents to dwell with her, let her not divorce him. 15. But if the unbelieving husband or wife separates, let him or her separate. The believing brother or sister is not held in bondage in such cases; for God has called us to peace. 16. But how do you know, O wife, whether you will save your husband? (1Corinthians 7:13, 15 - 16)
No one should ever stay in an situation where spousal abuse, either physically, verbally or otherwise, is present. If the offending mate was a believer at one time, they have BECOME an unbeliever because of their behavior. If the offender is not willing to seek counseling and make a sincere, concerted effort to change their habits and the situation at home, the offended spouse should not remain in this type of environment. Prayer about the situation and separation from the person is certainly warranted.