My (33M) wife (34F) came back lesbian after being in prison.

I have no idea what to do. She told me she's a lesbian now and that she had sex (I guess) with three different women while in prison. She was released on Thursday, she'd been in for a few months on a (second) drunk driving conviction.

I feel so blindsided, confused and betrayed. It would honestly be easier to deal with if it was a guy. Yeah of course I'd be mad and upset but at least I'd get it. This is alien territory.

To really top it off, she's not even sorry. You know how most people who cheat make a big deal out of how it was a mistake and didn't mean anything and they'll never do it again? It's like she doesn't care. She just announced this is who she is now like it was some amazing thing. And that I should be happy for her almost? It's so weird I can't explain it... she's been obsessively writing letters to her cellmate who's still inside (this was the main woman she cheated with) making plans for them to live together once she gets out in a couple months. She's sent 3 or 4 letters over the past couple days and even talked on the phone once. She stayed up all night writing to her.

And I am just... an afterthought. "Oh shit right I've got this husband of 5 years to deal with, well I'll just drop this bomb on him and it'll all work itself out somehow!" She acts like she doesn't understand why I am upset... she said I can keep the house and dogs so she doesn't get what the problem is. Wtf?

Oh and she went right out and bought alcohol after telling me. She was doing court ordered rehab as part of her sentence (got the prison term reduced by agreeing). I paid for this. I was desperate to get her help and she at the time was fully compliant. Now she's back to drinking. She says it's okay because she "learned how to control it". Bullshit. I'm an alcoholic too, I'll have been sober for a year on January 1st, that is not how it works!

I'm just so angry and devastated. I paid for her treatment, I stood by her side the entire time just like she stood by me when she demanded I quit drinking after I nearly got in a fight while blacked out on New Years eve. Then I got better his whole past year while she got worse. She was keeping booze in the house, invited me to bars and I still managed not to relapse (My mom was in the last stages of her terminal illness at this time and I couldn't afford to be a useless drunken idiot). Then she barrels through a schoolzone drunk in the middle of the afternoon, goes off to prison, decides she's going to be a lesbian after her cell mate seduces her, and wants to toss away our marriage after all the effort I have put in.

What the hell is the reason for it? Is she resentful of how I acted when I drank and this is karma in a way? Was she secretly drinking or doing drugs in prison and it's scrambled her brain? An early midlife crisis? Mental illness? I didn't do enough to help her recovery before things got to this level because I was so focused on myself? If I could have prevented this, then I don't even have the right to complain, and I'll spend the rest of my life in regret. If that's not it, then what is??

Thanks to anyone who has made it through reading all this. I'm absolutely lost. If anyone could help me make sense of what's going on in her head, or else just tell me what to do, please let me know? Thank you.

TL;DR: Wife went to prison and just got back. Suddenly she's turned lesbian, has no concern as to our marriage or my feelings on this matter, carrying on an affair with her cellmate, and is back to drinking. It's as if she was replaced with a different person. I'm in shock and have no idea how to handle this. My life is completely in ruins.