In-law In My Dreams

I've been happily married for better than 10 years now. I have two sisters- in- law. I've come across nudes of one on her laptop. The other, I found nudes on her phone. Neither of those were done intentionally, just by happenstance. I can't stop fantasizing about being with them. I've also caught glimpses of my mother- in- law in the shower or changing. She is also now in my fantasies as well. Roughly twoish years ago, I found myself creating situations where I could brush against them. About a year later I started patting out smacking them on the ass. I can't help thinking that they are somewhat enjoying the attention. Nothing has been said about it. I wonder about it though...