Secret Admirer Letter to a Married Man? PLEASE HELP!?

There is a guy at my job who comes and works here about twice out of the year for a couple of months (He is a contractor, I'll call him BILL for protection)...I first came across BILL about 2 years ago and developed a serious crush on him...I didn't think he felt me the same way, despite the stares he gives me as well as compliments on my outfits. So I never got the "balls" to ask him out... Fast forward...7 months ago a friend of mine saw BILL. My friend told me that Bill started asking questions about me, and that he thought quote "She is breath-takinly beautiful!) WOW...I grinned so hard, but at the time I was dating this guy, and BILL only stay at my job for a couple of weeks...Now fast forward to about a week ago...BILL is back at my job working. I ran into him in the hallway and he took my breath away! But I couldn't say anything more than Hi to him. I went to the break room to talk to my friend about BILL being back...My friend replied with "Oh yeah I talked to him and he said that he just got eloped and his wife is in Sweden and won't be back until winter". "NOOOOO!" I thought. BUT...My friend said that he asked about me AGAIN and said the exact same thing "She is so freaking gorgeous! Just so beautiful!"...Since then, I have CAUGHT him looking at me, and he has caught me looking at him, but I feel like now that he's married, he is trying to behave like a good husband, which I respect...But I can't seem to shake my feelings toward him...I thought that maybe a secret admirer letter would help do the trick in just letting him know how I feel (nothing creepy or disrespectful) and that I need to let him know so I can move on and not have this regret of never expressing myself...But does it draw the line because he's married? Please be honest and thanks so much!