My 27F friend 27F of 15 years told me she cheated on her husband and now I’m questioning if I should continue our friendship?

My friend casually brought up that she’s been cheating on her husband (they’ve been married just 6 months) by sexting and attempting to have sex with another guy. Not only does she not sound remorseful about it, she seems disappointed that the sex hasn’t happened yet. She doesnt seem to view this as cheating as they have only been sexting so far, and although despite attempts to have sex with him, it hasn’t happened yet. I’m shocked at the casualness of her explaining this as if it was exciting. I’ve been best friends (I was in her bridal party!) with her for the last 15 years and I never realized she was such a narcissistic person capable of betraying the one person she claims to love. It makes me wonder, if you can lie to and hurt your life partner, what can you do to just a friend?