This is more of just a sanity check, and I hope to god it is so ridiculous that is sounds like a shitpost.

And a short backstory on us. We were high school sweethearts that got married at 18 and are 48 now.

Last weekend I was out of town on a business trip and her work decided they wanted to throw their Christmas party early this year and had it that same weekend. I was a little bummed that I missed it because they are usually really fun and I like a lot of the people she works with, but no big deal.

Turns out my wife gets drunk at hooks up with one of the guys AT THE PARTY. Nobody caught them red handed but people noticed them being flirtatious and that they disappeared for a time. It was weird enough that I ended up getting a text from one of her coworkers warning me that something might be up and explaining the story.

So when I get back from my trip Monday evening I confront her about it and she admits to cheating. I tell her I will meet with an attorney this week to get the divorce filing started and I leave. She follows me crying saying that she is sorry and it was a mistake and so on but I still just walk away. I don't want to lose my cool or say anything I will regret so I leave without saying a word. 

Yesterday she ended up calling my friends and family, whoever she could get a hold of and tries to guilt trip them into taking her side (that I should leave her), and some how it seems to be fucking working.

Most (not all but still more than half) are actually siding with her. Telling me that I should throw away a good marriage over 1 mistake and that I should work towards forgiving her. And that I need to think about our kids, ect.

I am sorry but cheating is not "a mistake". You don't accidentally fall on someone elses dick. It is a conscious decision to betray the person you claim to love and destroy all trust.

Our kids are 26 and 24 established adults, they can handle their parents getting divorced.

So am I really the asshole for leaving my wife?