12 years!!! Maybe that guy just isn't for you and never was? If he hasn't come around to give you a good time in bed after 12 years of marriage then maybe you're just not each others types? Sometimes seeing the ugly reality of a relationship is one nasty and painful truth.
Time to move on perhaps? There's no extra points for being in long relationships that aren't working. I've done it and I'm never going to do it again. Compromises is one thing, but sacrificing something that is important for you isn't compromising, it's dying a little every day.
Life is short.
edit: Divorce isn't half as bad for kids as seeing the parents in a shity relationship. Never forget that they're likely to copy all your misstakes in life. You're a role-model for them. What kind of life would you like them to live? Being security addicts or taking some chances in life?
edit2: Never forget that it is his responsibility to make a conscious effort in solving his problems and hang-ups. He is commited to making you happy isn't he? If he isn't or doesn't even understand, then you should definitely move on.