My fiancé does not believe it god?

Hey guys, I recently became a Christian again after many years. Problem is, my fiancé does not believe in God. It really makes things hard for me, I know people tell me to break up with him but it's very difficult when you ha e already devoted your life, love, and future to someone. I pray for him but I don't want to force it on him. I feel like such a sinner for being with him but honestly I don't know what else to do, I feel trapped. What do I do?