I believe this is a 'prepare for the worst, hope for the best' scenario.
You will be likely angry. Perhaps in a way that is different from anything you've ever felt before.
Some possible symptoms to experience/expect:
Heart Racing
Body temp rising - esp around the head/face
Sweating.
Hands Trembling
Nausea.
Tension in the neck/shoulders/jaw.
Dizziness.
Clenched fists.
Perspiration.
There are probably more. So you need to recognize them and find a way to 'cook them' or digest them without suppressing them. This is not going to be easy. It will be in fact, very very very hard. But, if you can somehow choose to maintain that awareness, I think you could probably do this. Did I mention it would be a challenge?
The upshot is - you pull that off, and you are taking a big step towards losing reactivity towards your spouse (a good thing).
You maintain your high ground in a way that may completely shift the dynamics of things.
You can give a modulated response that is grounded and yet completely appropriate.
You might be shocked. Maybe not - you've probably read enough around here to be at least a little 'street-wise' about this stuff.
I think that the best you can hope for is to not let your anger take over everything else. If you can get outside of it and find a way to keep your bigger picture in mind, you have a chance at not losing yourself to it.
If you think about what comes up on this board so much - people react to their WAS walking w/ pleading, begging, crying, etc.. and it doesn't really get them much of anywhere. Later on, they begin to get a perspective and eventually they are (hopefully) okay with themselves. Perhaps moreso than they were in their M.
One big thing to ponder, re: infidelity. When a spouse violates their vows, they have violated their own integrity. Essentially they have sold themselves out. Vows are something we make to ourselves - its just we usually make them in a reciprocated fashion to another person.
Sometimes when someone violates their own integrity, our attachment makes us react as if we violated ours too.
So - don't let yourself feel diminished by someone else's lack of integrity. You have your own to maintain, and it's quite literally impossible for you to maintain someone elses as well.
One idea, which may be of use:
One way to prepare for this is to use your imagination in a focused way - kind of a very strange 'creative visualization' exercise -- get yourself physically responding to the stress of what you are imagining - stay aware of it and explore those feelings. What happens that's unique to you when you feel angry or hurt? How does it pop up in your body? Can you experience it, without a lot of 'chatter'? Can you be there with that discomfort and still know you are okay? Does it feel different than other times you've felt angry/upset/betrayed?
M: 32 W: 29 T: 9 Years M: 4 Years I hit rock bottom: 2/11 PA admitted: 4/11 WAW: 5/11 D filed: 6/11 now: Patience, wisdom, and growth - hopefully.