HELP!

I agree with Aimee... I think that maybe just sitting with a third party and talking about how each of you feels could really make a difference.  Good luck Andy and hang in there!  Just because things are tough... don't go having sex with someone else like many guys would do.  Be strong and fight for your relationship.  Good luck

What does she say when you ask her why she is no longer interested in being intimate with you?  Is she nearing menopause?  Sometimes, men start out conversations talking about themselves. "I need more sex.  I miss the closeness.  We need to work on this because I need change."  Perhaps if you ask her to talk about her needs, her wants, and don't put the pressure on her of hearing about you.  There is a reason she feels the way she does.  If she feels like the conversation is all about you and what you want, she may enter it with hostility, and nothing will be accomplished then. 

Besides seeking professional counseling, that leaves 2 choices.  Stay or go.  If you told her that the lack of sex was going to end the marriage, what would that do?

When you talk with her, have you explained that the lack of intimacy is HURTING your marriage?  Because if she isn't interested in saving your marriage, then that is the real problem.  That it is frustrating for you, but that it is endangering the marriage?