What does it mean for a girl to tell a boy that you are my eternal concern?

This shows that girls have deep feelings for boys and are reluctant to let go.

If one of the girls or boys is married, or has established a relationship with others, then the girl means to tell the boy, "I love you very much, and being with you will make me uneasy about you." I will often think of you in the future, whether you get up, what are you doing, whether you eat well, whether someone takes care of you ... I will care about you all my life, even if I can't be with you. "

If both of them are still single, the girl means to confess to the boy.