Ok, I am not going to go back and forth with you about medical stuff. Since you have posted here, your W has been sick almost weekly. I hope she gets the medical attention she needs. I understand living with chronic pain all too well and it is a terrible strain on a marriage. It is horrible for the person experiencing the pain. She has to be proactive though on getting help and despite the reason for her pain, there are options that sound like they haven't been explored.
Think about what you said... you are expecting too much too soon. Why is that? IMO it is because you have not detached from your W.
In order to have a healthy R BOTH individuals must work on getting healthy as individuals hence the need to detach and focus on you. GAL for a few months is not enough. It has to be lifelong even if you do stay married.