How do I tell her that her husband is cheating?

My best friend and I met in high school and were inseparable until two years ago. We shared each other's secrets, fears, challenges, clothes and successes.

About two years ago she met a man and told me he was the one she was going to marry.  However, the man she chose dated my cousin's roommate at university about five years ago.

The man had a reputation of chasing any skirt that came his way even when he was committed in a relationship. Indeed several times at the nightclub, I saw him other girls and not my cousin's roommate. When my friend introduced him as the man she wanted to marry, my heart sank.

I told my best friend she was making a mistake and that man would never be faithful to her. My best friend accused me of being jealous and ended our friendship.

My best friend and her boyfriend eventually got married. However, my best friend's husband is intimately involved with other women and I have spotted a number of times at restaurants and at beaches with his other conquests. I have even taken pictures.

I still value the friendship with my best friend and I really want to share this information with her, although she wants nothing to do with me.

What's the best way to handle this situation? Should I show my best friend the evidence of her husband's unfaithfulness? Should I confront the husband? Or should I mind my own business?

Roselyn