Oh Texassuccess, I hear your pain, your heart-felt pain. This is such a wrenching, devastating situation to be in. Not only do you see your beloved wife unraveling in front of you, now you must learn to be mother as well as father to two very small children. And pick up all the tasks that your wife use to do as well.
You are learning, making such good progress on understanding how you have been co-dependent and what you need to do. You show great insight in what you've written.
I think it is often true that the mind grasps the situation long before the heart does. So believe what you know to be true about what you need to do, and let yourself feel everything you feel without changing your path.
Do you have a support system where you live? There must be many community resources available if you can find out an umbrella organization to call to get you linked up. There are many practical aspects of your situation to cope with, and the more you can cobble together the resources you need, the better off you'll be.
Many of us find that there is really a higher power out there, so even if you don't believe in it, open yourself to the light around us, and ask for help, and more may come than you expect. Churches often have support systems that can help, even if you aren't a church-goer or believer. Perhaps you could locate some "pseudo-grandparents" whose grandchildren aren't close by, and would enjoy your kids.
Many more people will be around to respond to you post. Keep coming back, this is a safe and caring place to express all that you are feeling, and get a profound level of support.
ShootingStar1