Instead of looking at this as a problem, perhaps consider looking at it as an OPPORTUNITY. An opportunity to do the most loving thing you've ever done for the woman that it sounds like has burnt herself out trying to caregive you, carrying you on her back for however many years. Let her set you down. Let her. I promise you it will be the most loving thing you could do for her right now. Go get another oxygen mask a real one, not a wife, not even a single person, perhaps a more structured healing organization, if that's the kind of support you already know that you need. Look at it as your chance to be loving (to both her and yourself) and at the same time selfless for the first time. Things only happen if there is also an opportunity or opportunities for a way out.
Oh, and one more suggestion. Ignore the word divorce. It really doesn't matter. From the day before she told you, to the day after she told you, nothing really changed. Things were always this way or headed this way based on your own choices. All that changed is your awareness. This is actually a step forward. It's up to you how you handle it from here. It speaks to your character now and has nothing to do with her. This is about you. Take a few slow deep breaths, and go call a crisis line if you have to. All you have to say is help. They will help you get your legs under you now and they will be better qualified.
Forgive your self for abusing your wife's frail humanity this way. Forgive your wife for being human and having a limit and a breaking point. And do the same for yourself. Be really really gentle about everything right now and just go slow if you are feeling resistant. It sounds like you don't have to do anything really and she will likely be handling the rest of the stuff. But now it's up to you to decide what you are willing to do FOR YOURSELF. It's not about your wife anymore. You can't use her as your excuse to hide anymore. You can finally seize this opportunity to show her love though. This is your chance to learn how to be who you really are instead of a mere shell of who you are.
Yes, it's scary as hell, I'd like to welcome you to living and feeling. :) The truth really does set free, not a JW packaged "truth", but YOUR honest, living, breathing, real truth. Your honest emotional truth. You are not the first person to walk this emotional path. There is help from others that have both walked AND studied the path. I believe this is one of those times when, passing through your own personal "armageddon" you can reach a sort of "paradise" that you don't even realize exists. It's ALL an analogy, see? As a friend of mine once nicely summarized it to me, "it's always darkest before dawn".
I'm unfamiliar with your situation so I don't know if there is someone you could humble yourself enough to go be around or stay with temporarily while you give yourself time to decide how to process your new awareness about the real nature of your situation. Family, friend, even a sufficiently respectful enemy will do in a crisis like this. I hope you will keep us posted as to how you are doing and let us celebrate whatever steps you decide to take. Don't give up on yourself, okay. If you can let a broken woman go care for herself, there's hope for you yet. ;) Plus you seem fairly honest with us here and it seems to me that was a significant step. The cool thing about counsellors is that they are bound by law to be confidential so it can be a nice quiet safe place to hide for a while.
I hope you will give yourself credit for small steps like reaching out to others and even for becoming more aware of where you are really at now. I think your comment that you've seen her as your oxygen mask shows great awareness on your part and I believe there is a LOT of power in that kind of awareness. I don't feel sorry for you right now, I feel excited for you because I know you have a great opportunity here. If you've plunked along this far with such a challenging and limiting dynamic going on, imagine how great things can be once you've got much better oxygen reserves in place.
You only have to make one choice right now, then you get to simply ride it out. The choice likely has nothing to do with changing her mind. The choice may be how you are going to choose to manage this situation, giving up on yourself or standing up for yourself, with difficulty or with grace and whether you are going to take this opportunity to be loving. Love is not a feeling, it's an action. Start small but significant. You already know what you need to do.
And don't buy into anyone that would "label" you. There is nothing wrong with you. You are a normal human being responding to abnormal circumstances in exactly the same ways that billions of humans have responded before you and much the same as others will after you. Now that you are more aware, maybe try thinking of yourself as a mad scientist who's time has come to experiment and explore with other ways of living and being. Do what you really want to do. You are the one that will live with the consequences from here on in. Right now you are already living with the consequences of past choices and I respect that you have been so honest about how hard you have leaned on her to do your living for you. This honesty and awareness gives me hope that you will find your next step and your next oxygen mask until you are breathing again fully on your own. :)
The relief you will experience will really be worth it. The fears that you face right now are about to make you a very wise man, if you continue to embrace them. :)