I found the man of my dreams

I never believed love at first sight was a thing until I met him. It was as a picture, he isn't so much handsome or 6ft tall or filthy rich. But I admired him. Then, to when we met, I saw myself go to introduce myself to him at the ceremony, I felt uneasy when other guys approached me while he was around. 

Who is he? My boyfriend's brother.😢 Now, I have to force myself to let this feelings out. What if I can't? I planned to break up with my man because it wouldn't be fair to say I'm in love with his brother.