LB broken beyond sanity!

So I just played a game against LB, here are the things she did, #1 literally stood there attached to people and took away 80% of their life, #2 built AD, yes you heard that correctly SHE BUILT AD! On purpose, her final score was 25/7 and her damage while AD was 4x more then anyone else and more then ALL of her teammates(who were AD and build AD) combined. Now please explain to me how that's not broken?