I guess the thing is, you're not abandoning her, but letting her live her life. You said you love her. Loving somebody is not always rosy nor will it also return what you're after. And that's ok. It's not just about you.
You seem to want to "fix" her. You can't. But you can give her the space to figure herself out. In a normal relationship, even with friends, you'd call your friend on their behavior. You did that here. You gave the ball back and it's up to her how she'll handle it. It would be more of infatuation or ownership if you tried to control the behavior or her wouldn't it? You can do that with a puppy to an extent, but not a person.
What you're dealing with is not easy. But as you let go of things, and I suggest doing so one thing at a time, it gets easier to unravel the rubber band ball
For starters, how about letting go of the idea that your plan for your marriage and family is not going to go as you intended? Rather, it is what is and will be what it is going to be. One moment at a time.
Detaching is not abandonment. But since you're the last person that can get through to her, literally, you can show the family what you are made of and who you are. You have the ability to show your kids how to live. How to handle adversity with grace and peace. You have an opportunity to explore your own life to a degree not previously possible. To share your values with your kids through example.
That's a great opportunity, even if not asked for or thought of.
The best thing you can do for her is to let her live her life. You do not need to tell her you love her, nor that you care. She knows. Heck, even my ex knew that with me. I didn't realize it at the time, but later heard some stories from mutual friends. In case you think you can get through - my ex's friends ALL tried to talk her out of it. She ended up getting new friends. The drive is that strong.
So. How do you handle the situation? By being realistic about it. By figuring you out. You don't need to stomp or be angry or anything like that. If you were thinking of leaving, you would have to do the same things - detach. So, detach from the outcome of the situation. Identify and learn to control the things you can control. Namely, YOU.
I think you're doing it pretty well, to be honest. Many would have kicked her to the curb by now. You have a lot of resolve.
Mr Bond is right - detach. Stop looking to somebody who can't help their self, to help you or validate you. Ironically, the more you detach, the more you'll see what Mr Bond is talking about.
Play a nice course today?
AJ
"Our lives begin to end the day we become silent about things that matter" MLK Put the glass down... "Yesterday I was clever so I wanted to change the world Today I am wise, so I am changing myself."