If Jesus was resurrected and went back into heaven to be with His Father, then is that a sacrifice?

How could this have been a sacrifice when He never really died at all as He is God the Father at the same time as being Jesus the son and the Holy Spirit, none of which can die at all? So what kind of sacrifice is that? The bible says He gave His only begotten Son... No He didn't. Jesus is supposedly alive and well and in heaven right now! A sacrifice means death. You don't return from death. But Jesus did. I think God pulled a fast one on the Christians. (Trust me, I used to be a born-again Christian)