Between Us is Romance,

I only tell you,
the half of truth--
while hiding the half of lie.
I mention the details,
good to be known--
and hide the bad things you spy.
I tell you my great story,
give you my great book--
after hiding the missing pages.
I say that I'm honest,
for the sake of our moment--
but don't mention my previous stages.
I want to know You,
all that is you--
and only reveal one half of mine.
Know I can never love you,
but you'll always love me--
for You, the Half I design.
Who am I?