You can't force yourself to be in love. Feelings are not a choice.
Living a moral life hough is a choice . You can love without having to be loyal to your partner because you keep your words and promises. And that is a part of your moral code.
And perhaps your moral code is different and it is unhealthy for you to stay in the relationship. It depends.
It's not your choice really, it happens on its own most of the times, for some people hope dies last but we have to think about the mental health of those staying behind. If the person wakes up, they will figure it out and move on eventually too. Same for a person who has disappeared and their loved ones are unsure of whether they are alive or not. Sometimes you just can't live life waiting, time doesn't wait, it passes and changes things.
If that question comes in mind then it’s ok to move on. You’ve checked out already. You can still care for your spouse while getting emotional support for yourself somewhere else.