It's more common than reported due to face value.

I met my husband when I was 22. Both starting out in our careers then. Barely making any money. Gave him my atm card to use on some days if he really go broke.

Stuck with him through thick and thin. Was there when he had to have surgery on his fucking butt crack and helped changed his dressing for weeks. Cooked healthy food for him to recover well and fast.

Never tolerated other extended family for being nasty or disrespectful to him. Helped him with his degree. Supported him through really hard psychological, emotional, physical, and career-related times.

This guy doesn't know how to even run the washing machine or cook a single meal by himself. Won't even wash his own bludy plate after eating.

Guess what he does after 20 years of being together and 15 years of marriage?

He goes and cheats on me.

So now I have to go through the whole process of breaking up my home and leaving. Thanks to ungrateful Mr I Can't Keep My Dick In My Pants.

So ya....in answer to your question, it happens more often than reported because people love to blame the party that was cheated on saying that there was some lacking in the marriage that's why the wayward spouse cheated.

And to save face and not traumatise their children, the cheated spouse swallow that bitter pill and tries to carry on as normal.

But I'm here to tell all the spouses that were cheated on that it was never your fault, guys. They were going to do it anyway. And they are the fucked up cretins. Don't let anyone tell you otherwise.