The hint does not help. We've been stuck on this for hours
I will always see you within me.
Assuming the aphorism is,about close friends or lovers. 'We' are you and me, the letter 'w' is a rotated 'm', friends or lovers do complement each other while having a significant common base, so it makes sense to see the other upon introspection, looking from 'behind the mirror'. Metaphorically speaking one rotates the POV. On the other hand, watching one's image in the mirror, to some extent one sees what constitutes the other.