For better or worse, for richer or poorer, in sickness and in health... Wasn’t that part in your promise before Jehovah?
Yes it was. I’m not superman. Where is my breaking point? Am I supposed to stay until I reach it? At that point she will be lost. But if I leave she will be lost sooner. It’s a double edged sword.
I'm gonna do something here that sounds accusatory - it is not:
IMO She is but the catalyst in this - The problem is internal in you - Like blaming a rock wall for your inability to climb over it, if you know what I mean... If you can see her illness as an inanimate object (the rock wall), what can you do to gird yourself for a greater assault? It's a long climb... What can you do to limit your stress and receive required rest? Who can you consult to help you climb the wall? To teach you to climb the wall more efficiently? Outside of your service to her, you must serve yourself too, in order to have the strength to endure. Most folks sacrifice themselves till there is nothing left, but that only leads to destruction:
I used to be in a high stress business - It tested my breaking point daily. I used to start my day barfing blood... The pressure was insane. One of the coping mechanisms I found sounds completely silly, but it worked for me... 10:30 every morning, the phone was off, the watch was off, and I was sitting on the tailgate in the prettiest place I could find close to wherever I was... I would haul out a single burner camp stove, my old tin cup, and I would sit there and make tea. I know that sounds completely stupid, but yes, tea. No time... No pressure... No schedule... The ritual of it... waiting for the boil, waiting for the steep, waiting till I could sip it...
I found so much peace in those few minutes every day, that the rest of the day was magnified - It made me more durable - and even the ulcers went away... Such a blessing out of taking time for tea. So simple, so stupid, but it worked like a charm for me.
Now, I am not telling you that tea is gonna fix all your woes - But I am saying that you will be surprised what WILL work for you - cast about and find out what that is.
And don't forget God. He won't put something in front of you that you can't lick... Though you'll have to rely on him... But by all means, by any means, I hope you find the strength to carry on. Believe it or not, this too shall pass.