Divorce her, kill the mofo

I would probably immediately turn the entire bed upside down, throw the nearest lifeless object out the window, doesn't matter the size, knock whoever gets in my way firmly against a wall, and issue monologues in their faces that echo hate, sadness, insanity, weakness, rage, profanity, wit, etc. while possibly causing more physical destruction if it enhanced the process. This is of course all to create an extreme, emotional, and meaningful awkwardness and to vent my frustrations. I would force them to stay so that they can witness the effect on me and then leave them in the situation they created.  They would owe me that much, and that would be the last time I would look at either of them directly.

Afterwards, provided that I didn't induce a heartattack with my display, I would go rent a hotel room or stay with a friend, not parents as it would cause too much drama for me to get rest, and I would attempt to issue away all feelings for my wife and conjour all the memories of before I met her which didn't involve my friend to prepare myself emotionally for a single life so that I could relax in hopes of getting some sleep. Then I would give her the most frustrating divorce that she has ever had, depending on her mood and the situation this means I would either make her feel guilty and consent to giving her certain items that would magnify that aspect or I would take with me as much as possible. This is of course all in spite of whatever love we had, because relative to my normal demeanor, she probably wouldn't expect a situation so harsh, which would add to her regret. I would not ever take her back.  And I would never talk to my friend again.  I would then live life as if they never existed, regardless of my memories or feelings.  Internally, my potential for love and trust would become more callous as a result.

Honestly, that is probably what would happen. Whether it is the best approach or reasonable doesn't change what I would probably do. That wasn't the question.

i would beat the shit out of my bestfriend and then i would divorce her ass

But seriously, I'd kill both of them and his dog. Now, when it happens, CNN will find this post and say that I premeditated the whole thing.

I'd divorce her.

...

Well, it wasn't my best friend but I still divorced the fucking twat.

Honestly, you don't have the wherewithal to accomplish that much.

Mostly it just involves stunned silence. The anger, hate, withdrawal, that all comes later.

I can't even imagine what you must have gone through, Rocketpig. It must have been horrible. I don't even like to think about something like that happening to me.

Smash a bottle and ram it up my best friends ass...Sew my wife's vagina closed...
Then carry on with Fallout 3....Love them V.A.T.S :)

Yeah, it was horrible. The best part is getting over it and nailing more ass than you ever had before (and I never really had a problem with that to begin with).

Still, it doesn't take that "I've never cheated nor do I expect my partner to cheat" bit away from you. That stings like a manta ray's barb six feet up your asshole.

actually I do.  I've seen enough of my reactions in other situations to know what the immediate impact of being angry would be especially in a situation involving people that I care about.  I have a lot of control over my emotions, I simply allow them to unleash if the situation is justified.  I'm very passionate, expressive, intense, and opinionated.  My constant thoughts and mental organization has also allowed me to manipulate my own feelings directly, when I'm not unleashing some intense emotion that doesn't allow for such acute intricate manipulation in which case I would simply apply boundaries and try to guide it in some semi-positive way depending on the circumstance.  I think my experience in dance, art, sports, and especially acting has allowed me some of these abilities.  While my studies in psychology, spirituality, math, music, etc have allowed me others. 

Certainly there might be other factors that could change small aspects of the above but exactly how I carried out each second of every instance would influence whether those factors would be able to be prevented, be able to be bypassed, or if they would even come up at all.