3 Nephi 12:27-32, Earliest Text
Behold, it is written by them of old time
that thou shalt not commit adultery.
But I say unto you
that whosoever looketh on a woman to lust after her
hath committed adultery already in his heart.
Behold, I give unto you a commandment
that ye suffer none of these things to enter into your heart.
For it is better that ye should deny yourselves of these things,
wherein ye will take up your cross,
than that ye should be cast into hell.
It hath been written that whosoever shall put away his wife,
let him give her a writing of divorcement.
Verily verily I say unto you
that whosoever shall put away his wife,
saving for the cause of fornication,
causeth her to commit adultery;
and whoso shall marry her who is divorced committeth adultery.
Fornication is the physical act of sex outside of the marriage, in context. Christ is not justifying divorce; in particular, he is not saying you should initiate a divorce against an adulterous spouse. He is merely saying that if a man divorces his wife for any reason other than her own physical adultery, then he causes her to commit adultery (and thus brings her blood upon his garments), and that whoever marries a divorced woman commits adultery. There is no "out" mentioned for abuse. There is no way mentioned for another man to marry a divorced woman without committing adultery.
KJV and JST Matthew 5 is substantially similar to 3 Nephi 12 on this subject. And this teaching was repeated.
KJV Matthew 19:9 And I say unto you, Whosoever shall put away his wife, except it be for fornication, and shall marry another, committeth adultery: and whoso marrieth her which is put away doth commit adultery.
The JST of this passage is substantially similar. Unless it is because his wife fornicated, if a man divorces his wife and marries another woman, then he commits adultery; and whoever marries a divorced woman commits adultery. There is no "out" mentioned for abuse. There is no way mentioned for another man to marry a divorced woman without committing adultery.
KJV Mark 10:2-12
2 ¶And the Pharisees came to him, and asked him, Is it lawful for a man to put away his wife? tempting him.
3 And he answered and said unto them, What did Moses command you?
4 And they said, Moses suffered to write a bill of divorcement, and to put her away.
5 And Jesus answered and said unto them, For the hardness of your heart he wrote you this precept.
6 But from the beginning of the creation God made them male and female.
7 For this cause shall a man leave his father and mother, and cleave to his wife;
8 And they twain shall be one flesh: so then they are no more twain, but one flesh.
9 What therefore God hath joined together, let not man put asunder.
Which sounds an awful lot like Jesus is forbidding human-initiated divorce. The disciples thought so, too.
10 And in the house his disciples asked him again of the same matter.
11 And he saith unto them, Whosoever shall put away his wife, and marry another, committeth adultery against her.
12 And if a woman shall put away her husband, and be married to another, she committeth adultery.
Note - there is no "out" mentioned for adultery or abuse: human-initiated divorce and subsequent remarriage is to commit adultery. The JST of these verses is the same.
KJV Luke 16:18 Whosoever putteth away his wife, and marrieth another, committeth adultery: and whosoever marrieth her that is put away from her husband committeth adultery.
The JST of this passage is substantially similar. There is no "out" mentioned for adultery or abuse. A man who divorces his wife and marries another woman commits adultery, and whoever marries a divorced woman commits adultery.
To sum up that which is written:
*If a man divorces his wife for any cause other than her committing physical adultery, then he causes her to commit adultery.
*If a man divorces his wife for any cause other than her committing physical adultery, then if he marries another he also commits adultery.
*If a divorced woman marries another man, both she and her new husband commit adultery.
Notably missing from Jesus's teachings is justification for divorce for the cause of spousal abuse. The absence of this justification is consistent with the Sermon on the Mount. Read this in contemplation of applying it even towards an abusive spouse.
3 Nephi 12:38-48, Earliest Text
And behold, it is written:
An eye for an eye and a tooth for a tooth.
But I say unto you that ye shall not resist evil,
but whosoever shall smite thee on thy right cheek,
turn to him the other also.
And if any man will sue thee at the law and take away thy coat,
let him have thy cloak also.
And whosoever shall compel thee to go a mile,
go with him twain.
Give to him that asketh thee,
and from him that would borrow of thee turn thou not away.
And behold, it is written also
that thou shalt love thy neighbor and hate thine enemy.
But behold, I say unto you:
Love your enemies!
Bless them that curse you!
Do good to them that hate you,
and pray for them which despitefully use you and persecute you,
that ye may be the children of your Father which is in heaven,
for he maketh his sun to rise on the evil and on the good.
Therefore those things which were of old time
which were under the law,
in me are all fulfilled.
Old things are done away,
and all things have become new.
Therefore I would that ye should be perfect,
even as I or your Father which is in heaven is perfect.
Or, in sum, "all things whatsoever ye would that men should do to you, do ye even so unto them, for this is the law and the prophets." This applies even to the enemies, the revilers, the haters, the abusers, and the persecutors who we might be married to.