Looking for thoughtful replies on how to deal with my husband's "friendship" with his EX?

That is a tough 1! It seems like he's never really gotten over her. I'm sure he loves you, obviously! He married you but if I were you I would have a talk with his ex & tell her to back off! Just tell her how you feel. How would she like it? I could never share my husband, emotionally with another woman! You deserve to be his 1 & only! She needs to move on with her life. I wish you the best of luck!