Rhymes
Drive 4 25 is back
It's not about what specific action, it's about betrayal of trust and breaching what is expected. There are no rules that work for all relationships.
Impressive coming from you

I agree, cheating is only going to far according to the other's limits and expectations.
For my own couple, cheating is defined by "having sex more then once with another person" and relations involving emotions.
Ok .. not yet but I'm working on it........