Tough situation, but my advice is actually pretty simple. Jesus said that the second most important command that God has given us is to "love your neighbor as yourself." (The first one is to Love God with all your heart, soul and mind. See Matthew 22:36-40). He said that the entire Old Testament Law and all the instructions given from the prophets were based on those two commands. That means the old phrase "do to others as you'd have them do to you" is pretty important!

With that in mind, I’d ask yourself this: If you were this guy's girlfriend, what would you think about another girl professing her love for your boyfriend? I'm going to go out on a limb here and guess that you'd probably be pretty upset—maybe jealous, maybe indignant, but definitely not happy about it! If you really love her as much as you love yourself, you'll keep your feelings quiet for the time being.

A find though: If you're right that this guy has feelings for you, let him be the one to break things off with his girlfriend and pursue you. Don't set yourself up for embarrassment by venting your feelings for "honesty's sake". There's really no point. Proverbs 29:11 (NKJV) says, "A fool vents all his feelings, but a wise man holds them back." So keep your heart patient until the right time, sis. Wait for a guy who will value you above all others!