Is Telling Someone You Cheated Actually The Decent Thing?

Background: I've cheated and been cheated on. When I was a teen, in my first relationship, I kissed a work colleague on a night out while my then-girlfriend was at home. The next day I couldn't live with the guilt, fessed up and watched that person's heart absolutely break in front of me. It was sickening and defining at the same time: I knew there and then that I'd never cheat again as I could see the hurt it caused. It wrecked me for months and I even started to drink heavily to deal with the guilt, while also telling myself some BS about how 'at least I owned up' as if that made me feel morally superior when really it just did damage to another human that I cared about at the time.

I look at it differently now. Later in life (karma you might say), I was cheated on by a girl I really cared about and she fessed up. It absolutely destroyed me and still kinda does to this day. I've just woken up from an absolutely horrific dream about it right now that painted it all in a light I hadn't thought of before. And knowing it impacts you in such weird little specific ways you could've never planned for, as well as obviously destroying your ability to trust.

It's got me re-considering my stance about cheating and confessing. I'd always said that I'd rather know and make my own informed decision, and look if any of us had the choice where it was like "You have one unread message re: 'Cheating'"...we'd obviously need to know what that said! But is it ultimately kinder, when you weigh up everything, for a cheater to say nothing and be left with the guilt as penance? This is of course assuming there's no reason you absolutely need to tell the other person, i.e. if it was unprotected and they now need an STI test, if there's a pregnancy resulting etc. Is confessing ultimately a selfish act to try clear the cheater's conscience while it does way more damage to the victim?

If you want to stay with someone afterwards, feel guilty and like a scumbag carrying around a secret (because you have done a scummy thing) and let that erode your soul somewhat while you try spend your every waking minute with your partner trying to make it up to them. Let them keep their happiness. If you don't want to stay together, then break up with them and give them the "It's not you, it's me" spiel. They'll still be sad but people can deal with break-ups and you don't have to break them fundamentally as humans in doing so. I've had break-ups where I've had my suspicions that cheating might have occurred in hindsight, ultimately it's easier not knowing and I wouldn't like to now.

Plus we all tell ourselves little white lies about our partners, or don't ask questions, to keep that perfect little image of them in our head. Nobody wants to think of their partner being out with them on a cute, happy little date, seeing someone hot and unconsciously thinking "phwoar", but we've all done it ourselves. Nobody wants to think of their partner getting rejected by someone who just wasn't that into them before, but we've all got rejected in the past ourselves. We want to feel like we're going out with someone...maybe not perfect, but we don't necessarily want to see all those imperfections either and we tell ourselves/others a story that covers those imperfections and that protects the image we have of them. Cheating washes all that away in an instant and can affect how you view potential future partners too, how you can try trust them etc. We all know people who never recover from it: who go on to have toxic relationship after toxic relationship because they grow to have such a horrible attitude towards relationships, you can spot them a mile off on any dating site sure!

Or is it better to know and live fully in the reality of it all? Does being cheated on and recovering ultimately give you a strength, a wisdom and a relationship polish that allows you to re-evaluate how you judge and trust people in a way that'll mean you find a better partner in the future? Does it make it easier to get over someone in the long run by being able to write them off as a cheating scumbag, or does it make it worse and undermine all the happy memories you thought you had?

If you've been cheated on and told/found out, are you happier and a better person ultimately for knowing or did it break you? If you've cheated yourself, do you feel that telling/not telling was the right thing to do with hindsight and judging how everyone's lives turned out?