Why are people so contradicting when it comes to cheaters?

A cheater gets caught and expresses remorse and feels horrible

Replies: ''You're only sorry you got caught. If you're remorseful you would've confessed.''

A cheater actually confesses the next day, feels remorse and lets the person decide

Replies: ''Good but you only confessed to get rid of your guilt. You should've just broken up''.

A cheater admits to having no guilt about it or doesn't care

Replies: ''You still owe them an apology at least. You lack empathy. At least say sorry.''

I've never cheated and understand they shouldn't have done the cheating but it happened. After it happened there is no point in telling ''you shouldn't have done it''. It's already done. Why are they people on sites (esp on reddit, known for lashing out even if the cheater had a drunken kiss and reacting the same as if it was a long-term affair) so contradicting?

Why are people so contradicting when it comes to cheaters?
Post Opinion