Why does he all of the sudden stop calling and texting?

I've been in an emotional affair with a married man, I'm married also. We used to go places and spend time together but we work together also so we have to be careful at work. This has been going on since April. He used to want me to come to where he was living and go out to eat...nothing sexual...we started out as friends only. We do have coworkers though and have to be careful so no one will find out. But ever since Monday he's been ignoring me and won't call or text, or sext or anything....i've asked him what was wrong and he says nothing. He won't leave his wife but I have made it perfectly clear that I would leave my husband as our relationship is basically over anyway. I know I need to move on and I am. He works away from home and is only home on the weekends....he has said that he and his wife are basically strangers. So why hasn't he called? was it something that i did? If I ignore him and not call will that hurt him? HELP!!