While I wish for you that you could have the woman you desire, I appreciate the thoughtfulness of your wife's reply. You can't simultaneously wear the "Friend" and "Wannabe Lover" hats, because she's not into you. If you were her friend, you'd be happy for her when she's taken on a romantic picnic and kissed by a guy she fancies. It's a choice. Do you want to be friends? It can work. My brother is friends with his ex-wife and her new husband. He hangs out with them with his new fiance. Even the folks who encourage that--it can be sensible if a friendship preceded the romance--generally advise taking a break first.
