you are my wonderwall.

What wonderwall means:

Some one who you find yourself thinking about all the time, the person who you are compleatly infatuated with. the one that you look for on your buddylist everytime you sign online. the one who has a heart next to their name in your phone book. the person that you find yourself completely head over heals for.

or

Something or someone that is always interesting. For instance, when you lay in bed at night, you can stare at your wall and begin to notice all the little details that you wouldnt have notice otherwise. A wonderwall reflects your greatest thoughts and emotions.

or

..is basically someone you can lean on no matter what happens and they will always be there for you. It could be a friend, family, or a lover. it is someone who cares about you so much and thinks about you all the time.

Someone that saves you from yourself. Like your superhero or savior. When you feel like you're just stuck in a hole, it's your wonderwall that saves you.

But in the simplest word:

The one you want to spend the rest of your life with, your only reason for life.

:)