Why the missing words when I listen to flyleaf?

How come when I listen to Flyleaf and try to keep up with what she's saying with the lyrics I find on yahoo she's saying stuff that isn't wrote down? ... it didn't start out as a big deal but now it's bugging me becuse they should be there.

That is common with a lot of Artists and songs. What is published for the lyrics is not always what they say. When they submit a song for an Album the record company requires them to submit the lyrics for it. Often between when the lyrics are written down and when the artist performs the song either in studio or live they change it around to make it sound better. Hardly anyone bothers changing the written lyrics. The Record companies don't really care as long as they have a hard copy so they can say 'See, this is what it was suppose to be.' Incase of any legal disagreement.

... I don't know if I'm allowed to reply to my own ? - sorry I'm new - ... That seems strange for a songwriter to let the lyrics be changed then not edit what they had sent into their company, but I don't know anything about stuff like that so I don't know... The thing I was really worried about is sublimital messaging ... I know it sounds weird but if I can't tell what exactly it says I get a little aphobia of it ... I just wanted to look into it ...

It happens a lot. Music artists tend to change lyrics at the moment they sing. It always happens, no worries.