If you are Catholic you should have gone through marriage preparation classes with your Priest. I would tell your bride the facts the best you can explain. Before marriage. Take the test .Pray and ask for insight and do what's right in your heart . If the child is yours.
Only the Lord can forgive and forget your past present and future. Others sometimes have problems and cannot forgive and forget. A marriage is like a tree . You feed and water it.You hold up one side when the wind blows from the opposite direction. Your spouse does the same when the wind blows at your side . If not the tree of love and marriage could snap. I know my ex spouse only wanted me to hold on to the whole tree. It snapped and fell. Just one mans view. Good luck and may peace be with you.