What do I do if My Wife cheated on me and gave birth to someone else's child?

We have been married for two years but our interview was before we hit the 2 year mark. She was heavily pregnant at the interview and I thought it was mine the whole. Eventually she tells me she cheated and she doesn't think its mine. The child is not mine and I don't know what to do. I want a divorce but I'm worried about my status. I filed an EAD extension and that's still pending. What are my best options moving forward?