It isn’t over because they cheated. They cheated because it was over.
Infidelity is an effect, not a cause.
Ask people why their last or biggest relationship ended, and “my partner cheated” is one of the most common answers.
But this is a head-in-the-sand answer; an omission of the truth, a denial of causes leading up to it, in which they were likely personally involved. It’s pressing “play” on their relationship history only at the point where things came visibly unhinged — pointing only to that moment in time when their partner stepped out of line, but never at the moments (many) leading up to it.
As though people cheat in a vacuum. As though they were in totally happy relationships but lost their minds one day and decided to throw it all away.
Notice, however, that when “cheating” is cited as the answer for why things ended, it’s always that “they” cheated — never that “I” did. Because people actually doing the cheating don’t cite “cheating” as the cause — they cite the reason before the infidelity, which was the real one.
Why it really ended (i.e., exactly the same as “why people cheat”)
Look, okay. On the one hand: it’s many reasons.
There are a million and a half explanations as to why things fall apart — countless, infinite rationalizations people offer themselves and others when they do this.
But there’s also only one. And it is, simply: because one or more needs weren’t being met.
Boredom, maybe. Novelty, put differently. Ego-stroking, or conquest, for the insecure. Gray-area line-blurring subjectivity, like massage happy endings or strip clubs, perhaps. Heavy drinking and loss of judgment, maybe. They felt undesired, or unseen; unimportant to their loved ones. They feel young again, or respected. They laugh for the first time in years. They’re narcissistic. Or just lack empathy.
Whatever. The specifics go on and on.
But the real reason relationships end in cheating — and the real reason anybody cheats —is because they weren’t happy.
This is to say nothing about the legitimacy of that “unhappiness,” let alone the effectiveness of cheating for dealing with it, but it is the truth.
Your relationship didn’t end because they cheated. They cheated because your relationship was already over.