Most Helpful Guy
Ask yourself why you are so attracted to him. I know it's very hard at this stage, but what are your instincts telling you? They are telling you something. I am NOT talking about your heart which is going gaga over this guy. I am talking about the things that are nagging at your soul, the questions, what you REALLY see in this guy.
Think about this: How much can you really love him if he is flirting with other girls? Surely you have not made the way you feel clear to him.
Love is a deep knowledge of another persons heart that is forged from years of being around each other, talking, sharing lives. Not observing someone from afar and thinking that you are correct in everything you tell yourself. That is a recipe for pain.
My advice is to get to know him. Learn what makes him tick. Stay abstinent from sexual activity. If you date him for a while (A few years) and he is willing to wait until your honeymoon to be intimate (Thus telling you that you mean enough to him to wait. Otherwise he's saying you don't), and you know that you want to spend the rest of your life with him, then perhaps he is your true love and mate.
But you cannot know that now, especially if he is still flirting with other girls, and truly has no idea what he himself wants.