I think she's struggling with boundaries. Maybe there's a codependency issue going on. It could also be why she's remained friends with you. She needs an anchor in her life and is unable to get it for herself or her partner.. so she's getting it from you.

Why does it matter what's happening in their relationship? How do you feel about her wanting to reconnect with you but then bailing out because of this guy? She's using you. I'd be more concerned about that.

Her issues are not yours to figure out. I doubt she's even a good friend to you.. so what are you hanging on to if you have your own life?

Are you lonely, bored, hopeful..? Think about why you've invested time into all this.