Is repeating a song that contains a meaning that life is dedicated to a beloved person instead of God considered disbelief, taking into account the ignorance of religion at that time?

A repentant person should not dwell on the past to avoid waswasah (whispers from Satan), for one who repents of a sin is like one who has no sin. And the statement "I was created to live for you" is an exaggeration, excessive, and false, because humans were created to worship Allah alone, in accordance with His saying, the Almighty: "And I did not create the jinn and mankind except to worship Me" (Adh-Dhāriyāt: 56). This statement does not reach the level of disbelief, unless the love of the created being is like the love of Allah or greater, then that is shirk (associating partners with Allah). As Ibn Al-Qayyim mentioned, 'ishq (passionate love) can be disbelief if the beloved is taken as an equal to be loved as Allah is loved, or more. The sign of this polytheistic 'ishq is prioritizing the beloved's pleasure over the Lord's pleasure.