God is able to do what we can't do, and even when a situation seems impossible we should pray and ask Him to intervene. As Jesus reminded His disciples, "With God all things are possible" (Matthew 19:26). Pray for her, and pray for yourself as well, that God will change you both.
At the same time, from what you say your wife's attitude is very firm, and she doesn't seem open to changing it. I wish I could promise you that God will intervene and change her mind but in all honesty I can't, because God seldom works that way. God warned Jeremiah that in spite of his prayers and his preaching, his hearers would remain unchanged because "these people have stubborn and rebellious hearts" (Jeremiah 5:23). When we make decisions even bad ones we alone are responsible for them, and we alone must bear the consequences.
But let me ask you a question: What does God want to teach you through this experience? Will this draw you closer to God or will you become bitter and turn away? Will you open your heart to Christ and let Him change you or will you reject Him?
My prayer is that you will commit your life to Christ and become His follower, whatever happens to your marriage. God loves you; He loves you so much that He was willing to send His Son into the world to die for you. Turn your life over to Christ today.