Tell me what causes two people who once loved each other to divorce?

Many couples divorce because small frictions in life cannot be reasonably resolved. The main reason is that both of them lack tolerance and cannot consider problems from the other's perspective. When encountering problems, no one is willing to give in. In fact, in the final analysis, it is mainly because the two people no longer love each other. The relationship between them is already very weak. No one is willing to tolerate someone they don't love. When some small problems arise, they will be infinitely magnified and become unsolvable. conflicts, leading to breakup.