Well, the one that I can think of is that men and women had no intention of taking an oath of celibacy for the rest of their lives when they got married, and then found themselves in abusive relationships.
Considering that masturbation is as deadly a sin as adultery (it's ALL inappropriate contenteia - masturbation, fornication, adultery, gay sodomy), it doesn't make any practical difference from the perspective of sin if people remarry and thereby commit adultery, or stay unmarried and touch. But it sure makes a GREAT DEAL of difference when it comes to human suffering.
The Church has taken the stance that Jesus has taken the stance that people who have to escape abusive marriage have to be chaste and celibate for the rest of their lives because they, unfortunately, married a beastly person.
No.
No people will not do that. Historically, they masturbated alone and sad for the rest of their lives, and thus committed mortal sin in that way. In more modern days, people decided that's ridiculous and chose to remarry in pursuit of their own happiness. The Church chose to stand in the way, and so the Church has been kicked to the curb on this matter and is almost universally ignored, and rightly so.
Perhaps Jesus really did set up an impossible rule that magnifies human misery, in which case we sinners will sin, and hope he forgives us. Adulterous remarriage is the same sin as masturbation, but it is much more comforting and much less miserable to have human companionship.
Maybe the Church is right and Jesus intended to compel the unfortunate in marriage to endure the lifelong misfortune of celibacy thereafter. People have freewill and they are not going to obey him on this, any more than there is any normal teenager who ever abstained completely from masturbation until marriage.
"Be perfect" he is said to have said. Human beings are completely incapable of that degree of sexual perfection. Show me a normal male who says he never has masturbated, and I'll show you a mortal sinner - for lying is the same degree of sin as adultery and fornication and masturbation and homosexual sodomy: mortal. At least according to Jesus.
People are not going to abstain from sex for the rest of their lives because they were abused by their spouses. It doesn't matter what Jesus said: people are not going to obey that, just as teenagers are not going to abstain from masturbation.
The question, then, is what the Church is going to do. Eastern Orthodoxy permits remarriage after divorce, as an allowance to human weakness. The Protestants permit remarriage. The Catholics do not, but have tried to create a lax loophole for "nullification" that makes it "Catholic divorce-lite" in some cases, in some countries.
The Orthodox and Protestant solutions seem to disregard Christ. The Catholic solution seems to disregard reality and compassion to rigidly adhere to what Christ is said to have meant by what he said.
What's the right answer? Everybody has an opinion. And people are going to act on their own judgment, so it almost doesn't matter. When it comes to this subject, people are going to make their own decisions, and words are wind.