
Alissa G. answered 04/30/19
M.A. Spanish; Language Expert with Experience Living Abroad
Hi! I love this question and I know this song :-). In this particular phrase, que means "that", so the phrase es que yo sin ti = "it's that me without you". The more you study and listen to native Spanish speakers, the more you will notice they often begin sentences (in colloquial speech) with Es que... It's more or less like saying, "It's just that..." or "The thing is..." in English.
I hope this helps! I love that you are so curious about the grammar used in song lyrics. I was the same way when I first began learning Spanish!
Cuídese.
Alissa G., M.A. Spanish