My [M25] now ex-girlfriend [F28] just sent me an accusation message out of nowhere

I woke up today to an insanely long message from my now-ex, accusing me of all kinds of things—cheating, deception, gaslighting, and even spell work (yes, really). She claims she got an anonymous call from someone who “revealed everything” about me, even though she just got a new number and barely anyone has it. She went on a rant about how I had multiple side pieces, manipulated her, controlled her free will, and was basically deceiving her the entire time. She ended by saying she’s blocking me, changing her locks, and threatening a protective order if I ever contact her again.

None of this is true. I never cheated, never lied, and all I did was go to work and come home. The fact that she believed this so quickly, without even questioning where it came from, makes no sense to me. I wanted to respond, calling out the inconsistencies, pointing out that none of my friends had her number, and saying that if she wanted to break up, she could’ve just said so instead of creating this whole dramatic story.

Now, I’m wondering—should I even bother trying to reach out to clear the air, or is this just a lost cause? It’s obvious she’s convinced herself of this, but I’m not sure if she’ll ever realize how ridiculous it sounds. Should I just let her believe what she wants and move on?

(long message is in comment section below this post if you’re curious) (as well as my potential reply)