i had to agree with snowblind in the beginning. that statement says alot about how you were feeling." i would be gay" when it comes down to it recognizing who or what you are will come with time. it doesnt have as much or anything to do with your wife, other than how you choose to live your life. yes you might love her and yes it might hurt her to tell her how you feel, but really if you were gay it would end up hurting you both more to deny who you are. and that goes for the kids that arent in the picture yet. there are alot of men out there that remain married but are online or cruising dangerous places looking for sex. the decision is yours and you will end up making the right one for you.
i was your age exactly when i said to myself that yes i am gay or at the very least bi. so i went with the bi thing for a while because just like you i wanted kids and a "real" family. after a while i realized that i still wasnt being honest with myself and had to admit to being totally gay( to myself ) now i am really glad that i didnt produce children(i still think about it sometimes though) or get married and then divorced, things just worked out for the best. i now have a partner of several yrs and wouldnt trade it back for anything. he does have kids and was married. i still got my family in a way, and my real family was totally accepting of me and any partners that i ever had. not everyones story has turned out as well but you will figure it out. dont rush it, you are only 19. you have a long life ahead of you.