To think cheating is understandable if your partner lets themselves go completely?

You leave the marriage then. You don't cheat.

I can see why they might want to, but there's no excuse for doing it - they should leave

Again, none of this excuses cheating, it just acknowledges that people often avoid hard conversations or decisions and that avoidance sometimes leads to bad, damaging choices. I think it’s worth talking about why that happens, rather than pretending everyone acts rationally when they’re unhappy.

Your original premises was that cheating is understandable where attraction has faded. You have continuously been told that that's not true. Your attempts to justify it are trying to make it an almost inevitable response. Again, thats not true. Your logic is flawed, you're at odds with reality. You can try to justify it to yourself all you want but you won't persuade anything that it isn't a choice and it's the wrong one.

Echoing what others have said. Leave them if you’re that bothered.

OK, so this isn't personal, it's just a philosophical debate?

It's just that it sounds like a personal experience. A more open and less personal question would be, for example, 'is cheating ever justified?'.

Yes relationships do decline overtime.

Thats nothing to do with cheating.

Cheaters cheat because they think they can. And they want to maintain their status who because it benefits them. But they also want to cheat.

Cheaters don’t suggest open relationships because they want to maintain their status quo. They want the benefits they have from the relationship so lie and deceive their partner. Thats love of even respect.

They do it because they believe their needs and wants are above everyone else’s. It’s that simple. Relationships ending are understandable. Cheating is simply selfish

I think there’s a lot less nuance than those who cheat like to claim there is. “She doesn’t understand me”; “the marriage died years ago”; “I’m only staying for the children”…

No matter what the background, it ultimately boils down to “I wanted to so I did.”

That want overrode all other considerations.

I have seen so many decent people hurt by lazy, selfish partners who prioritised their sexual urge over love, commitment, family, respect and loyalty.

If you can cheat, you can leave. Cheating is the lazy, cowardly option. Having your cake and eating it.

Cheating is never ok , even if the other person did the same . You can do the right thing and choose to leave . You never have to cheat

It is not complicated OP. Relationships and emotions are complicated. Cheating is an action and a choice.

Having your cake and eating it is the phrase that covers the question 'why do people cheat'.

YABU and your attempt at logic is a joke.

Too emotionally paralysed to leave but not to jump on someone else’s cock? 🤣 get a grip.

And your other reasons, hoping things will change etc, also a load of shit. If you’re hoping things will change you don’t do that from someone else’s bed!

You’re a complete cunt if you cheat, point blank, simple as. If you’re not happy, leave. If you aren’t prepared to leave then it’s not had enough to warrant jumping into bed with someone else to “wait and see if things improve” or because you feel sad, what a load of shit

Lots of waffle from you trying to get people to give you permission to cheat on your partner. Just leave the poor sod.

Some people gain weight owing to an injury or from taking meds. It isn't always cut and dry.

Yes okay there are complicated feelings in relationships. But the way you act on those shows your character.

The only situation in which I think that cheating is morally acceptable is in relationships where there is abuse and the abuser has therefore made it unsafe for their partner to leave readily, and essentially destroyed the relationship anyway through their own actions (if someone abused you they have broken their vows/the relationship in my view).

The emotions behind cheating are not 'layered' lol. They're pretty basic actually.

What about the years of hard conversations once it’s found out?

Or the hard conversations about why you won’t leave your unhappy relationship for the person you are shagging?

What about the hard conversation every time you lie to your partner about where you are or who you are with, who you are texting?

What about the gaslighting you will do if they suspect? Is that not as difficult?

Do you mean someone stops making an effort in the relationship?

It's not hard to understand why someone cheats OP. It's because they see benefit to themselves at the expense of their partner. It suits them to use their partner for money, childcare, housework, whatever. It's a selfish and destructive decision but it's not a mystery by any stretch of the imgination.

Are you wonder why someone cheated on you instead of ending the relationship?

OP, I think your attitude shows that you are both immature and have low emotional intelligence.

The point of this thread was never to promote cheating, it was to unpack the messy, human reasons behind why some people end up making that choice instead of leaving outright. Not all behaviour is excusable but most of it is understandable when you look closely.

imo it simply comes down to ‘because they think they can’

Somehow cheating on their partner makes them feel good. Maybe they feel that having two women competing for them makes them irresistible. Maybe it’s fulfilling some needs of theirs. Excitement. Whatever.
For that to happen they need to first think they can do it and get away with it. They need to see themselves invincible enough that they can cheat and still keep their nice cozy marriage. Just like people shoplift. Go over the speed limit etc….
And then they need to comfortable with taking the risk of hurting their partner and children.

YABU. If you would rather be with someone else other than your partner for the reasons you describe, or any reasons really, you should leave them.