Prepare to have your mind blown.
It seems all of our eyes are deceiving us. Sort of.
Pink, it turns out, is actually just the combination of all other colors of light, minus green. That's why, according to the video below, pink should really just be called "minus green."
While you can obviously see pink, the explanation for its absence makes sense. Realistically, it's not a color of the rainbow, and that should say enough.
Check out the video below for the full explanation, especially if you still don't believe.