"The right thing to do" typically feels very uncomfortable.
I strongly suggest you not share your husband with any other woman. You have more respect for yourself than that. The best thing to do is give him a choice:
"H, I will not live in an open marriage. Either break off all contact with OW and work on our marriage or I will file for D."
This approach has the best results.
"What is best for my kids is best for me" Amor Fati Link to quotes: https://www.divorcebusting.com/forums/ubbthreads.php?ubb=showflat&Number=2879712
