I don't want to be the reason he ends up in a marriage with one of OW.
Um no. You're not the reason. He makes his own choices (albeit some very odd ones that most of us would disagree with).
I highly suggest you not take more responsibility for choices than are rightfully yours. I also suggest stepping away from the FB posts. Nothing good comes from that. For you. (I get the humor aspect, but really there's nothing there worth reading about ya know? )
Peace, AJ
"Our lives begin to end the day we become silent about things that matter" MLK Put the glass down... "Yesterday I was clever so I wanted to change the world Today I am wise, so I am changing myself."