Why am I here ?!

I'm pretty sure it's the Secret Window with Johnny Depp. A fantastic movie I recommend it, a real brain teaser.

Isn't it a song lyric?

YES I FOUND A KERMIT THE FROG VERSION FOR YOU HERE
https://m.youtube.com/watch?v=ylDBf7o_YtM

After watching the movie I can confirm that Johnny Depp does say this line
IMDB agrees with me http://www.imdb.com/title/tt0363988/quotes