Difficult crossroads wrought with peril...?

My wife and I have been married going on 5 years and I've recently discovered that I'm really unhappy with our relationship. I started talking to a friend of ours who as it turns out has quite a lot in common with me and Being bored and unsatisfied where i am currently, i find myslef feeling very alive when talking to her. I never was really all that attracted to my wife and i had been hurt pretty badly in the relationship i was in prior to getting married, so I married my wife for her personality thinking that one day I'd really have a deep desire for her. Now we're 5 years (no kids) down the road and I'm thinking that maybe I made a really bad mistake. The relationship is boring and dull and the is terrible. My wife is a good person though and i really don't want to hurt her, but i think that as long as i'm with her i'll never really be happy. I'm lost and don't know what to do.