I'm sorry you're having to deal with all of this but glad no one got hurt. A lot of alcoholics are masters at hiding how much they are really consuming. I'm glad she is in rehab, I just hope she is really wanting to quit herself. Only time will tell. Don't worry about the rehab romances. Like PP said, you have no control over what she does. If she hasn't been promiscuous before it seems unlikely that she will start now. My RAH went to rehab for 3 months and they kept the men and women pretty segregated. I'm sure if someone really wanted to get together with another they could make it work but at least where he was at it would not have been an easy thing to do. I don't even think they had any group sessions together.
I'm sure you are in shock. I confronted my H and even though he had been an A for many years I never thought he would've needed rehab, after all he had quit on his own before. But quitting sir king involves so much more than just stopping the substance. It is really only a small part of addiction. Once he was in rehab I realized how much he really needed that and how without it he would've either taken many years to deal with his dysfunction or he may never have been able to stay sober. He's been out for a year (he did 90 days and needed all of that...) and doing well. He is vnsry closely monitored and and to do sober link 4 x a day. He has really turned around his life a lot. However in our case it took many years to get to that point and really for me to hit rock bottom. Our relationship has taken a big hit. Even a year later I still struggle with a lot of resentment and anger.
Know that at this point there really isn't anything you can for for her to help her. She need to focus on herself. And you need to take care of you. I'm sure it is very overwhelming to be in the position you're in relatively sudden. I thought that him quitting drinking would be all it took and then everything would be fine and dandy. The truth is much different however and it will be a tough road more than likely. Get into counseling with someone who has an addiction background and educate yourself on addiction. I'm a medical provider and am appalled at how naive I was when it came to addiction. I wish I would've known much more about it. But the alcohol was a secret and literally no one knew but me.
It sounds like even though you are very angry (and rightfully so) at what your wife did, you still very much love her and care for her. Some of us here detached so much over the years that it is hard to come back from. Try not to focus too much on how to help her because really this is her gig and her gig only. Presumably she will get an in depth psych eval that will reveal any underlying issues (because the vast majority of addicts have other known or unknown underlying issues that they are self medicating ) so that she can get the help she needs. Check out alanon so you can meet others in similar situations (and come here). Because even though friends and family will likely be supportive, they really don't get this unless they have lived this so it is nice to have people you can really relate to.
Also once the dust has settled a little be honest with your girl about what is going on (if she doesn't already) . She knows something is up and better be honest (age appropriately ) then let her come up with her own reality. Because this is your life right now, and even if she stays sober it will play a big part in your life for the foreseeable future and trying to protect your girl from the truth will only hurt her in the end.
I wish you and your wife the best of luck. It won't be an easy journey but if she is committed to getting clean she will likely come back a different and improved person. Just don't expect everything to be normal right away because you will both need to figure out what the new normal will be. You can't go back to the old normal. And she will never be able to touch alcohol again and should probably avoid narcotics at all costs as well in the future. It won't be easy but it can be done, but for now just take one day at a time and focus on yourself and your kids. Your wife if being taken care of.