Ah yes, I remember that article now. I have a hard time with some of the DB advice because it decidedly did not work for me and frankly felt wrong from the beginning. Ultimately I did reconcile with my now H and it certainly was not because I was his friend while he was cheating on me.
Yes, detachment is your friend. It is imperative. Have you read this article ? It really helped me understand the how and why of detachment.
In my experience, my BF was willing to live in the basement and continue his A with OW while I was upstairs, miserable. Things did not turn around for me until I realized that I deserved better and acted accordingly. I packed a bag for him, took his house key off his key ring, and told him to GTFO. When he moved his stuff out I certainly wasn't home and didn't help him move a single thing. He wanted out so it was his responsibility to make that happen. I wasn't rude or mean, I simply wasn't available to him anymore.
If you love somebody, set them free. http://tinyurl.com/2empx2g