I really fancy my friends wife

I 35m UK, have been friends with this guy since our teens. He has an amazing wife who is really hot, before they got together we had a brief fling. I meet them regularly and have a really good relationship with the wife. I can't help check her body out and remind myself how we had a great few months together years ago. We had a party a few weeks ago and she took a lot of pictures on my phone (I have a better camera) for the wider group to share, but there are some she took it appears just for my eyes only. I have asked her about it privately and all she did was smile. Not sure if I am being led on here or should speak more about it with her. Help Edit..... Hasn't taken long for the comments to convince me this is a real bad idea. I think this issue might have occurred due to my recent split from my GF and it coincides with my friend and his wife hitting a rough patch. I'm staying away and deleting the photos.