Lyric discussion by Chromas 

Cover art for Mirrors lyrics by Misery Signals

I've always found that the song is about the speaker being mesmerized with someone, who then took advantage of the power they had over him, turning him into someone that they like, rather than who he is "Beautiful, this life you drove through me" He later realizes that the person who is changing him is just like him, "...Through this wall of glass" ( a mirror). He begins to hate the person that he's become, "violent, the life you drove through me," and he sees that he can be anyone he wants to, in the last stanza.

At least, that's what I've always taken from the song.