What does "I shake it off" mean from Taylor Swift's song?

[Clovis.Mendonca]

Hi, guys. I think you know that song. When Taylor Swift sings "I shake it off" what does she mean with that?

Here it is the lines:

Heart-breakers gonna break, break, break, break, break
And the fakers gonna fake, fake, fake, fake, fake
Baby, I'm just gonna shake, shake, shake, shake, shake
I shake it off, I shake it off

Shake it off, I shake it off,
I, I, I shake it off, I shake it off,
I, I, I shake it off, I shake it off,
I, I, I shake it off, I shake it off


I've heard "shake it off" means forget something, let it go.. BUT, I read on the Internet that in this context shake if off does'n mean it. It means "I don't mind... I don't care what people says about me"

I'm so confused now... which one meaning is it correct?

 

[SoothingDave]

She doesn't let it affect her.

https://englishlessons.wordpress.com/2014/06/13/idiom-of-the-week-shake-it-off/