metalchick, thank you. I'm not ready to leave her over something sudden (however traumatic) that developed over the course of a month, but I'll take up your advice to look for a meetup or some kind of outside support. I'm also having dinner with a friend soon with the intention of discussing this with him. We've helped each other through previous periods of trouble, and I think he's capable of hearing me out and keeping everything private. I can't keep complaining about being lonely and then not reaching out.

I've explained thoroughly to K that I'm not happy with any of this, and that her continuing will cause me considerable pain, but that I trust her to make the right decision for her own development and for our marriage. The co-worker is also stressed and guilty about this, and is relapsing into disordered eating, and I hate that she's suffering through this too. I'm trusting K to come to an equitable solution. If she doesn't, I have to brace myself to deliver an ultimatum.

Because dang it, you're right. I love the heck out of K, but I deserve better. Thank you.