Lady Gaga herself worships Satan. Now, Lady Gaga uses her songs in bringing youths to hell, to where Satan belongs! Lyrics matters too. You use songs to tell anyone what's inside your heart. This has only one meaning that will summarize everything: satan is in her heart, not god.
But I still believe that God can change her someday because it is said in the Bible the "WHATEVER IS IMPOSSIBLE FOR MEN WILL BE POSSIBLE FOR GOD." C'mon!