AITAH for trying to ignore my “friend’s” engagement?

My ex college roommate (23F) and I (25F) had a big blow up in college. It ended with me saying “I don’t think you like me very much. And I don’t think I like you at all, so let’s just get through this year”

Fast forward two years, our other roommate is getting married and to my SHOCK, I am asked to be a bridesmaid. The other two are very close, and that’s totally fine with me. It’s two weeks before our roommates Bach trip and one month before my sister’s wedding. My boyfriend and I have a custom ring picked out but know that there’s a lot of other friends and family who’s time it is to shine right now. We are waiting till after the bach trip and after the family wedding so that we can have our moment while letting everyone shine in their own light.

Two weeks before we are supposed to leave my ex roommate (23F) face times me out of the blue (we have not talked in two years one on one) and let’s the camera open on her ring. I’m like “um, hey?” And she proceeds to tell me her engagement story top to bottom. She then wraps up with “anyway just wanted you to have a heads up before the trip”. She knew that we are pending an engagement. We don’t talk one on one. It was so bizarre. I was pretty hurt that day, just kind of having it rubbed in my face, I have no idea why she called me. I certainly wouldn’t call her let alone invite her to the wedding if we were engaged. Of course I want to be engaged. But I am happy to wait a few months so we can really soak it up.

Fast forward to the trip, she keeps bringing up her engagement. (This is literally another girls Bach trip). And I’m blocking this out of conversation, trying to change topic because, girl it’s so not your moment. She confronts me saying that she felt shut down and I simply said “I don’t know if it’s appropriate for us to celebrate you right now”.