For some reason I don't like that phrase. It makes me uncomfortable to say so I don't. I also feel it may be overused and no longer means as much as I think it should. Here are some alternate combinations of words that mean the same if not more.
  1. You're my best friend
  2. You're my favorite person
  3. Life is better with you in it
  4. You're always my first choice
  5. I'm here for you
  6. How can I help?
  7. I love you, specifically
    Okay, yes it is I love you. But it means more when you can feel that it is love for you and you alone, not just anybody