my life gone to shit

this came out last week, but theres been alot going on so the last day i finally had time to process things, my wife in the last few weeks has been very secretive.  taking her phone everywhere she goes, bathroom bed everything, so i have been joking with her, what are you doing there and she would just laugh and say nothing, so then last week she says we should have an open marriage, i was like umm what, she kind of joked and told me she wants me to be happy and she knows i am not, so i do some checking, and i find out she has been texting non stop a person, so i inquire who she is texting and she tells me none of my business.  so i ask if it is a guy or woman, she wont answer, she again says she wants an open marriage, and then tells me she is talking to another guy. i have two kids, so i try and remain calm, and we have had some issues as of late due to stress in dealing with a 12 year old with aspergers.  Tuesday night she confesses to me she has be sexting with this guy, now, normally i would have exploded, but i am being nice due to my kids we talk i bitch, to her, she doesnt seem to care, i have this guys number and i tell her i will call his ass, she says she told him i would say and do that, and he would deal with me himself.
 
holy fuck who is this woman in front of me and this guy she is sexting with, now to make matters worse my wife was having surgery on wednesday, so i have to put on my game face to be strong for my kids and not open my mouth to my inlaws cause no matter what i do, they blame me, so in the end i know they will say this is my fault.    so i let it slide but its been bugging metoday when i went to see her in the hospital i told her before i go back to work on the 10th of dec, we are discussing how we are ending this, mostly to not hurt our kids, and i want her to out herself to her mother without blaming me and we have to figure out who is moving and all that good stuff, 
 
to go back a few days on tuesday i texted her to remind her of something and she tells me she does not want to hurt me but she has led such a sheltered life, (BTW her mother did it to her not me)  that she is not seeing what she has been missing and wants to see where it takes her.  my wife was overly protected by her mother, her and my brother in law both, if they could not do it, there mother did it for them homework anything did nto matter, so my wife relys on too many people to fix her issues, she does not know how to handle alot, in the last 13 years i have tried to get her to be more self sufficient but alas  she went over the deep end, 
 
now my main focus is not hurting my kids, my youngest is 9 she is the strong willed one, and she will be ok i think, but my 12 year old has aspergers, and i dont want us splitting up to cause her a setback so this is gonna have to be treated delicately
 
i do know i cant work this out with her, talking to others is one thing sexting something totally different,