I'd recommend you read "No More Mr. Nice Guy," and check out their website. Like me, you are TOO nice, and you haven't done a good job at letting your wife know what your needs are, and then STANDING UP for yourself.
It took me 25 years, but I finally figured it out, with the help of everyone here. Whether or not it works in THIS marriage, I still do not know, but those skills will SURELY help me in my next relationship, if this one doesn't work out.
You're staring at 20, 30, 40 years of stewing, silent resentment if you don't learn to do something about this NOW. Either leave the marriage before you have kids, because you appear to be sexually incompatible (what most of us are trying to tell you), or -- if you want to fight for it -- then STAND UP FOR YOURSELF.