Dealing with my ex's new girlfriend

So, situation update: ex got a new gf and I just have a lot of thoughts and feelings about it. His new gf called me and told me about it. I just told her my side of the story, told her good luck and gave her a fair warning. Me and her talked a good while. It made me feel a bit better knowing that she wanted to tell me herself and wanted to talk it over and be honest with me about it which I appreciated it and told me that she thought of me like a sister but tbf, she didn't really know what happened. When I heard it through somebody else, I felt a sting, I felt a bit hurt, a bit angry, and felt a form of betrayal. When me and her met, I was with the ex at the time and me and her had an instant connection. It felt as if we were good friends. I wasn't sure how she felt till just now. I just don't know about it now. For a while, I felt as if I had lost her. I just don't want to get my hopes up too high. I just dk what direction to go in. What is a good decision to go in? Should I forgive her knowing only one side of the story and not knowing that I got hurt by him? Should I continue being friends with her knowing that she accepted to be dating him? Should I just keep my distance for now?