So kinda a small situation with a lot of moving parts and people(using fake names to protect identity) so I do apologize for the length of this.

So my Partner, (Mary) and I have some friends, that we have been friends with for a while(Dave and Steph) that we hang out and do outings and bbq gaming, things that friends do with each other. And recently my Partner had meet someone(Mark) and just had really good conversation and starting to develop a connection. Well recently, it all came out that Steph and Mark have been seeing each other for a while unknown to all Mary and myself! So when it came out Mary immediately put the brakes on everything with Mark out of respect for Steph, but Steph feeling hurt and betrayed has now cut all ties with Mary, and blocked her on everything and not even wanting to hear her side of the story, which is causing Mary tho think and feel, like what did I do wrong.

I’m just looking for advice as to what can I do to support my partner Mary and help her through this and if she is doing the right thing to try and save her friendship with Steph.

Any and all advice is welcomed as I’m trying to look out for my partner