When people comment on infidelity on sites like this one, the most frequent reaction I read is "If he/she cheats on me, it's the end of the marriage/relationship, I quit!" Well… you know what? That's what you think but I only half believe it. It's a theoretical answer to a theoretical situation, but when it really happens, things are totally different.
Allegedly, about 65% couples stay together after discovering an infidelity. Do you think you know better than them? Well, you don't, if you have never had the experience of discovering you've been cheated on. How To Heal A Relationship After An Affair
I can tell you what will happen if you discover your partner is cheating: You'll be awfully angry (possibly to the point that you will struggle the urge of assaulting the cheater physically!); you will be terribly sad and disappointed; you will ask yourself "What's wrong with me? Why does he/she feel the need to look elsewhere?"; and here's the least appealing: you won't help trying to picture in detail your partner having sex with someone else.
I can also tell you what won't happen if you deeply love your partner: you won't instantly stop to love him or her. Depending on what happens next, you might get out of love later, gradually, but not overnight.
So, during a long period of time, several days, weeks perhaps, you will have to live with a series of overwhelmingly strong emotions that are sometimes contradictory and that will make it impossible for you to think properly, let alone make any meaningful decision such as "I quit" or "I'll try to salvage the relationship". And my point is that you can't theorize on how you will effectively act in such circumstances.
Here's a true story, which I'm sure won't ring true to many readers who will think I'm making it up, but I guarantee you it's real: A very dear friend of mine, very balanced and reserved, discovered that after over 10 years of a happy marriage, her husband, having his typical midlife crisis, had a sexual fling with a much younger and particularly attractive woman. My friend was obviously devastated and undergoing all the feelings I described above. She was seriously contemplating a divorce, even though her husband, who had made abject apologies, appeared to be sincerely remorseful and even though she sensed he was not really emotionally involved in the affair. Against Cheating: A Man's Perspective
She had cried, she had terrible outbursts of anger but they had managed to talk the matter in an adult way. Yet, she was still resentful and was giving him the cold shoulder to say the least, limiting communication to the necessary minimum. Nonetheless, she couldn't decide what to do: there were very good reasons to call it quits and there were equally valid reasons to stay and attempt mending the marriage (notably the fact that she still loved him, despite all the resentment and the loss of trust). Her husband had mentioned he was willing to salvage their couple but acknowledged that she was the one who had the final say about that.
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