My friend became close with the girl who ruined my life last year. Am I wrong for not being over it?

Last year a girl in my friend group started a rumor about me that got around the entire grade. It was bad enough that I ended up talking to a school counselor and stopped speaking to pretty much everyone involved. It took months to feel normal at school again. This year I made a new friend and things were going well until I came back from being sick and found out she'd gotten close with the girl who started everything. I told her what happened and she said she got it. But they're still close and I'm expected to just be around both of them like nothing happened. A few days ago at lunch the girl said something dismissive to me in front of everyone and I said something back and walked away. Now my friend and a few others are saying I need to let it go, that I'm being too sensitive, that the girl has changed. I started thinking about whether I was actually holding onto something longer than I should be or whether being told to get over it by the people who didn't have to live through it was just a convenient way to make my reaction the problem. I also thought about what I actually wanted from my friend. Not for her to stop being friends with this girl necessarily but for her to at least acknowledge that what happened to me was real and that my reaction to being around this person made sense. I realized that the thing bothering me most wasn't even the girl at this point. It was that my friend kept choosing to smooth things over instead of actually having my back. Every time it came up she redirected to me being difficult instead of acknowledging that the situation was genuinely hard for me. That felt like its own kind of thing separate from the original drama. Talking it through helped me separate the two things I'd been tangling together. The girl was one problem. My friend's response was another. We agreed the best next step was to go to my friend and tell her directly that I wasn't asking her to end the friendship but that I needed her to stop telling me to get over something she didn't have to go through. Just that. Not a big confrontation, just one honest conversation about what I actually needed from her.