Do I confront a family friend about my husbands infidelity?

I've written before about my husbands infidelity! Lately I've been unable to get his last mistress out of my mind! I looked her up on the internet and found her myspace page and facebook page. I saw her pictures and read some of her information! Didn't leave me with a good feeling at all! Then I noticed the watermark on some of her pictures! Professional pictures - I think she models? Anyway, the pictures were taken by my husbands friend sometime last year! I recognize the backdrop and it's in his home studio. Oh, did I mention that he lives around the corner from us! It bothers me, because I wonder if my husband was there when the pictures were taken but more than that. This photographer friend has always been welcomed in my home, he's been a surrogate uncle to our son, I've even confided in him before when he asked me how I was doing because he know I was upset and my husband and I were having problems. Do I mention what I saw or do I just leave it be! I can never respect him again because how can you be supportive of me and my husbands marriage and then help him cheat on me and be supportive of his mistress as well?! I've been trying to get over the affair because it's been over only for a short time but I have a hard time letting go! What do I do, say something or let it go!