Musical rules seem a bit ridiculous.

Hi everybody.
I am a music composer.
The music that I composed has been copyrighted by another business with this song. I filed a copyright complaint and was advised by lawyers that I should cooperate with the other business. They told me that I should sell the copyright because there is no possibility of getting it back. But this is the song that I want to dedicate to my wife. It's terrible isn't it when this problem occurs, can someone give me some solutions?