THIRD UPDATE - AITA for leaving thanksgiving dinner without explanation when I saw my ex there?

Hey everybody, this is just a quick update about the whole situation.. To the people who commented on my last post and told me to tell my friends and close ones about my ex best friend and her relationship with my ex, just in case she tries to spin the story, you were right. Nearly 4 days ago, she made a post on FB about me. Recently, a close friend of mine had found it and forwarded it to me. (I rarely use fb and she's still blocked on everything. That's why I didn't know anything.) I'll just paste what she said because if I explained it myself and put details, this'll be very long. She said:

"My best friend of 16 years had left me. After everything I did for her and after sacrificing my life for her, this is how she repays me... I should have seen this coming, but it caught me too much off guard. I didn't even do anything wrong. She blocked me on everything and I haven't heard from her since.. Everyone... Don't trust anyone too much, especially those who are close to you. You don't know if whether they'll betray you or stay by your side until the end. ___ (me), you're such a backstabbing bitch. You ruined my life forever and I'll never forgive you."

This is the same woman that fucked my ex. First, she invited him to thanksgiving dinner in hopes that we'll reconcile. Then, I found out that she has been with him for a whole year. And now this? What level of delusional is she on? No, and she EVEN had the audacity and confidence to call me a backstabber AND say that i was the one who betrayed her. The worst part is that people seemed to believe her in her comment section without even knowing the full story. Most of them were her friends (I know them but they aren't my friends), the others were people I don't know. They spoke bad about me and wished that something bad will happen to me. She's playing the victim card, spreading lies while I'm here, STILL processing everything.

I really hate that woman so much. I don't know what to do now but I'm thinking of responding to her. I've never in my entire life made a post about someone, let alone respond to their posts. So if anyone has any advice of what do I say or do, im open to hear it.

Edit: It's nearly 1am in here but I'd like to say something. Almost all of your comments are either telling me to give her a taste of her own medicine and stuff or telling me to just ignore her and let her say whatever she wants to say. I appreciate all of your comments (I'm still gonna read the others after typing this) both the petty ones and the opposite, (idk what to call it) but I think it's best if we give it some time. I'll think about it for a few days and I'll update you all.