New here but have been a voyeur

[pearlharbr]

You're the one who keeps allowing this to happen. You were advised to go dark and yet to continue the hours-long conversations. H is obviously not ready, willing and able to commit to the M and yet you are acting like he is. You are allowing him and his actions to dictate how you feel and how you act.

If continued involvement with OW is a dealbreaker then state your boundary and enforce it. "H, I will not live in an open marriage. Your continued involvement with OW is inappropriate and unacceptable. I cannot stop you from communicating with OW but I will not have a relationship with you while you are still involved with her." And then follow through.