Hi Bryan. I am saddened at your situation, and, unfortunately, it is a common problem in the world today. But I'm also saddened by the short sighted answers you've received so far. Let me explain.
Marriage is the hardest thing you'll ever do and God does not take it, or your vows, lightly. I believe God thinks your marriage is worth saving. You are now "one flesh". Whether or not your wedding included the scripture, "Therefore what God has joined together, let no one separate," it is still a warning to heed.
Remember, Satan wants to see you separated. It dilutes your witness and distracts you from your life's purpose, i.e. to glorify God. I've been married forty years and my wife and I have undergone TREMENDOUS difficulties that shook our faith and tore our relationship apart. This is what marriage often is. But all this had a purpose. After decades where she and I fought (sometimes together, and sometimes against each other) trying to fix the issues in our life did we finally understand God's lesson. Only when we gave it over to God and trusted that He will make it right did resolution finally come. Your marriage is worth the battle. Your wife needs to come to Jesus. This may be the road the Lord is using.
After reading the advice above I was shocked that no one mentioned prayer.
My advice to you would be to start by renting the movie The War Room and watch it for the first (or maybe the fifth) time. The message of the movie is clear: Your wife is not the enemy. Satan is the enemy. Prayer doesn't help win the battle--prayer IS the battle. To win this one you will need: 1) A strong and loving church family 2) A dedicated group who will pray daily for your relationship and her salvation 3) The will to pray, pray, pray for God's intervention. (It might be years or decades before God gives the victory.) You also need a plan, i.e. a permanently dedicated time and place for prayer and an organized methodology for praying, i.e. a prayer journal where you keep track of what requests you've made, how long you've made them, what God has taught you through your prayer time, the answers you've seen, etc. 4) FAITH.
Also, copy out Ephesians 3:20 and place it in a very prominent position. Read it and meditate on it. "Now to him who is able to do immeasurably more than all we ask or imagine, according to his power that is at work within us..." God will honor your requests. I know it. And also realize that this battle will glorify God.