There are actually steps a couple can follow to open the previously mono coupling to an open one.
This site is great. I heard the owner of it speak last year. She is a counselor who focuses solely on poly relationships. Look at the links in the top left corner.
Love withers under constraint; its very essence is liberty. It is compatible neither with envy, jealousy or fear. It is there most pure, perfect and unlimited when its votaries live in confidence, equality and unreserve. -- Shelley
me: Mags, 59, living with:
miss pixi, 37