To be quite honest, cheating is relative.
In my opinion, I don't cheat, because my heart belongs to the one I love. If I go elsewhere for service, albeit cheating in some peoples eyes, I don't see it entirely as such. I like to experiment while my SO does not. I like variety. Etc, Etc ....
I've heard it said, if you imagine someone else during sex with your SO, that is cheating as well. Very hard to define.
I personally don't always equate sex with love.
My SO would be hurt is she knew, no doubt, but I also KNOW she would understand. Our relationship is full and we share very special feelings.
I know it sounds like rationalizing, but I feel real cheating is when you are carrying on a relationship outside of the one you have, where feelings (love/like) are there. I try NOT to see the same SP over and over, because to me, that would be starting to push my own comfort level, and borders on cheating by my definition.
I will now prepare myself to be flayed, drawn and quartered.