I Don't Know

Whats wrong with me? I like someone who is much older than me (or so I thought since I dont know the exact number he is). More importantly, I found he is attractive since the day we first met. He is one of my company client. He talked to me in gentle way even I know he isnt gentle at all. He likes to make a joke and laughs like it was the funniest thing that he ever listened. And he is so tall, compared to mine. When we walked side by side, you could tell from a far it was father and daughter walking together haha.
I dont know why I think he is attractive. Im totally introvert. I dont like people invade my character, and he is the opposite of me. He talked to me alot, telling me what he does, his life, his stories, and many more. I just noded and shyly smiled responding his talk.
Or is it karma? I remembered back then, when he did the gentleman gesture to me and I talked to my friends telling them this story, I said "If he's single, I would definitely fall for him!" and so am I.
But I dont have the guts, because I know what did we do is just work related, nothing more. We just barely talk about work stuff, we never talked about anything else. There's no sign of us liking each other, its just one sided and it is me.
"Congratulations for your wedding!" a single status from my collegues makes me numb. Showing everyone who follows him, if the man that I like is getting married. Yeah, he's getting married to the woman that I dont know. Both of them showing a genuinely happy smile. I want to cry, but what was that for?
I am nothing to him and so does him to me. There is nothing between us. Just a little thing he did makes me feel I am someone special. Just a stupid thought that I had maybe he thinks I am special to him, meanwhile I am just one leaves in those trees. I am no different to the others, I am completely moron.
I tried so many times to type something to congratulate him, but nothing was sent. Is it my fault? Would be something different happened if he knows my feeling? Or is that what people called love? Or is that only likes? Or I am stupid calling its a special feeling?
I don't know.