Fireman, this is about broken trust. Not the specifics of the physical act.
Are you saying you would feel less betrayed if some guy gave your wife oral but not intercourse? I doubt it. Each of you broke trust. This is something you can either forgive, or not. There is no 'degree of offense' in this, your male 'friend' is an idiot and probably hot for your wife and stirring the pot.
The only questions that should matter is: do you love each other? can you forgive each other? do you think it will ever happen again?
"Yes, yes, no" is the only combination that will work. Talk it out with each other, resolve the hurt, don't rug-sweep. Good luck.
Second thoughts can generally be amended with judicious action; injudicious actions can seldom be recovered with second thoughts.
--Cyteen by C.J.Cherryh