Most women do not understand how important sex is to a man. Men live for sex. It is built into them (I am a woman)
Let me ask you some questions
Does your wife orgasm during sex? If you think she does have orgasms do you think she is faking them?

The whole point of sex is to orgasm and most women do not. So really what is point of sex if you know you are not going to orgams?

She may not feel appreciated. You may have very young children. She may secretly want sex but not with you. She may have a fantasy life in her head of what she wants and it is not happening.

What if you threatened to divorce?

Cheating is never the answer!! You must divorce and find someone who understands- though a lot of women do not. They think they do but don't!

I don't want you to lose your house, your kids, etc. but if she is not having sex with you at 30 years old, will she when she is 50??

I have been divorced, had kids, and without getting into a lot of discussion know both sides to this issue. And if I could have I would of had an affair when married!!! But I did not have time to meet anyone.

You need counseling with her, if she won't go, get rid of her. However, if you do get rid of her, she may find someone else that she DOES have sex with regularly!!