hmm I have heard it said that some divorcees or those whos relationships broke up because of some petty differences (maybe from the guys perspectives) but from the female perspective it was often something majorly wrong, like abuse, or indecency...infidelity, unfaithfulness
Or maybe it was people didnt want to actually say what the abuse was and try to downplay it (she tried to kill me, she went off with my best friend, he hit the children etc)
All people ask is that person to stay faithful or loyal to them right? If that doesnt happen then the marriage is over and broken.
For a lot of people thats a big ask that this one person is the ONLY person in the entire world they will ever see and speak to and love. You love someone or someone else is going to make that person jealous.
If you love your children more than your spouse, or your job, or you put anything before them, even for some people God or religion, they are not going to like it. If you side with your mother or theres then thats going to grate too.
Ive heard that some get jealous if their spouse so much looks or talks to someone else of the opposite sex. If you the type of person who people easily fall in love with maybe thats going to be a problem for your spouse to keep the others away even after marriage cos flashing your ring may not deter some people.
anyway just my thoughts. Solomon had many wives why? He couldnt just stop at one. Abraham and David and Jacob did too.