I would look forward to 10 years of becoming a new person outside "that" relationship. One can look at the why's, what's, etc., but it just is. Were I you it would henceforth be something else. Trying to figure it out is a waste of time. Look forward to a new life without having to worry about it. I know it is not quite that easy, but it is a choice between more of the same or something better.