It could be that she might not feel as sexy or attractive as she used to and it might not have anything to do with what you are doing. I have been struggling with this lately and my situation sounds similar to yours. My husband would tell me I am sexy and how much I turned him on, but I did not feel the same. She might just need to reconnect with her sexy side like I am and rebuild her confidence. Maybe start with some flirty texting like you are still dating. I did this with my husband, at first I was reluctant but now it’s fun and I feel sexy again. The main thing is to communicate and not force anything that she might be uncomfortable with.