You could file for divorce based upon incompatibility. Nevada is a no fault state. The judge isn't going to interested in why you want a divorce (unless you have children under 18) just that you want a divorce because your "likes and dislikes are so different that you can no longer live together as husband and wife." That is the definition of incompatibility.
Your other option is to see if your wife will go to counseling or maybe a doctor. There may be some physical reason for her behavior.
Some people who fall out of love still stay married, because sometimes it's just simply easier to do so. That decision will be up to you and your wife.
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