I just found out my friend of ten years has been hooking up with my recent ex.

My 22f friend let's call her Celina (22f) and I have known each other since 8th grade, we were deskmates for the last term before going to different highschools. We stayed in touch during the holidays and would hang out and it's been like that since. I considered her one of my closest friends.

We went to the different Universities but in the same area, like our campus was 15 minutes walk away from hers and my hostel was 5 minutes walk away from hers. She knew who my ex (at the time my boyfriend) through pictures and brief encounters. My ex knew of her but he never really cared to remember my friends in detail (or so I thought).

Now months ago I broke up with him, it was not a clean break, the relationship wrecked me and I recently started therapy because of it and other issues. Celina knows I'm still healing from that relationship.

Yesterday I was scrolling through my WhatsApp and saw Celina's status in a very familiar background, after I did a double take I realized it was in fact my ex's house. I immediately asked her and she didn't deny it. Apparently they bumped into each other in January at a new year's party and started talking from there. One thing led to another they went back to his place that night and have been seeing each other since.

Then she added that I broke up with him so I shouldn't be bitter about it and just be happy for her. And that he's been really good to her unlike her ex (they were together for 8 years and he cheated on her) I just stopped answering to think about what to even say as I didn't want to start a fight over my ex.

Any advice on how to move forward?