My gay friend keeps on ignoring me.

Good day. I have a problem. I'm in 3rd year college.I have a gay friend, we know that he's gay its just that he's not yet confessing to us. The way he moves, we already knew it.He's been my chatmate eversince we're 1st year. I always asking him about assignments and we're always chatting each other everyday.When we were 2nd year, I found out that he has a boyfriend. I am only the person who knew it. Our other classmates doesn't know it. I talk to him about it and he told me to keep my mouth shut.Out last conversation on Facebook last week is good, he seems enjoying talking to me. He's the one who's making topics. Things are different. Then suddenly the day after, I chat him and then "seen" and I chat him again and "seen" "seen".Until now he keeps on ignoring me. What did I do? What happened? Can someone give me a clue?