Your situation is extremely common, mostly because narrow minded people have misused the bible to define gay people as filthy sinners. As an ex-ex-gay PK I can assure you that owning the real you is the most fulfilling thing you will ever do, outside of maybe having your children. Because of this oppression of gay people, society has long forced men and women to live in denial and grow up and get married. Thus, many a heterosexual has found themselves betrothed to a latent gay or bisexual spouse. This will become much less common when religious zealots are no longer able to control the legal rights of gay people and then gay couples can marry and "drain that swamp" of the well intended but self deluding homophiles that get caught up in this tragic Un-American, un-Constitutional majority abuse of a minority. Now see how my gay marriage isn't a threat to your straight one, but in fact strengthens your marriage? I have a fantastic marriage to a awesome guy 20 years and counting, and that isn't bad for anyone else it's in fact good for all of us. As for you my brother, no one is 100% straight or gay, god made us all a little less that exactly anything. I have known many, many guys in your situation, and there is a rainbow of choices as to what to do. Many guys live a lie until their kids grow up and then sit their wife down and tell her. Many guys tell their wife right out and face the intense but surprisingly brief (it's never as bad as it seems like it will be) "dramatic reorganization" of their and their families lives. This is likely the most emancipating approach for you personally, and in many cases if your wife really loves you and you're truly friends, this approach can be amicable and very successful. May I recommend you contact you local chapter of PFLAG (Parents and Friends of Lesbians and Gays) http://community.pflag.org/
Many of the members are ex-spouses of gay people that have come to empathize with the unfair predicament that their ex was a victim of. There are as many varieties of "what to do now's" as there are people like yourself.
Sexual identity is a very powerful compelling force, otherwise do you think anyone would be willing to "come out"? Harvey Milk was assassinated like Martin Luther King. There is something to the statement; "To thine own self, be true!", because if you're not the real you how can you really be a good father for your children? As for you wife if she doesn't want to remain in a celibate marriage, although this does happen sometimes, an annulled or divorced woman whose husband turned out to be gay is a very sympathetic figure among straight religious single men, i.e.; she'll live. As for your parents and brothers or sisters and relatives, co-workers, paper courier and everyone else in your life, it won't be a cakewalk but you will be surprised how quickly you will find yourself so much happier with your life, and when you accept yourself as you truly are, others will fall into place. My extremely religious Mother Just joined my husband and I for Thanksgiving, and after years of preachy if polite and condescending posture, was someone I didn't recognize, open minded, totally changed in attitude and has come to completely accept me as god made me, and she adores my wonderful Catholic husband and has accepted him as her son. Believe me if she can open her mind, ANYBODY CAN! All I can say as someone that went celibate for two years of missionary street preaching and sincerely attempting to be "ex-gay" ( I was know as father Monte in High School) twice, you need to keep an open mind and consider all the angles, starting here; http://www.truthwinsout.org/
. You should also read; "Stranger at the Gate: To Be Gay And Christian In America" by Rev. Mel White. Be well my friend, Shalom and Maranatha and see; http://thedogfatherblog.blogspot.com/