What does "I love you" really mean?

It means that I accept you for who you truly are, with all your imperfections and flaws.
It means that I would do anything for your happiness; it doesn't matter about my feelings, it's about yours. As long as you are happy, I am happy.
It means that I can't go a minute without thinking about you, and you constantly occupy my mind.
It means what it means: I love you, really truly love you, and I will never leave you or let you go.