Would you finally cut off friend?

I have a female friend, that in our childhood to teen, was actually a very good friend. She is married, lives in another state, has 3 children, 2 of them are adults, and she is living in a "loveless" marriage where they supposedly have an understanding and stay together for financial convenience. She has claimed for years that they are divorcing, they never do, and both have outside the marriage relationships. One of her current relationships is coincidentally a man we both went to elementary and jr. high with, who also claims he is in the same marital situation, excluding kids (he has none), he too lives in another state. They have been driving and even flying back and forth meeting. His mother is even friends with my own mother, as we (me, my own mother and the male cheater's mother) live in the same rural town. So, as I have never appreciated, nor agreed with my female friend's lifestyle, now that I have to hear of their adventures through his mother, it is becoming even weirder. I haven't physically seen my female friend in years, but we did always call, text, email and years ago mailed actual cards and letters (before internet). I am so disappointed in her I am ready to just let what friendship we had go. I guess I don't have as much ill will towards him as he has no children. So, would you continue what friendship we have? I haven't contacted her in any manner in weeks. She texted me today and asked what I've been up to, I never replied.