I agree that "telling" on yourself, meaning after it happens, is an incredibly selfish act and actually worse than the cheating itself in a lot of ways... but it is/was still absolutely cheating whether you tell or not.

Talking about it and getting agreement/permission beforehand or having a conversation after you get caught (whether she found out or you told her) and getting that agreement/permission, on the other hand, is what takes it out of the realm of cheating.
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Asp