I agree. Have you tried 'romancing' her? Take her out - maybe somewhere special to the two of you (where you had your first date/wedding or something). Do the whole hearts and flowers thing and make her feel special - not just once, make it a regular thing, a weekly 'date night'. Give her a reason to dress up and feel good about herself - with no pressure to have sex! Maybe a glass of wine or two and the right atmosphere will encourage her to open up and talk to you, but find that spark you had when you first got together.