Should I p on the girl of my dreams?

Well, I liked this girl for three years now. We are good friends but are not close friends. It's very clear she likes me as a friend but I am 99% certain she doesn't think of me as more than a friend, and she is currently in a relationship. Ever since I've known her I cannot even get the thought of dating other girls in my head. Few girls, all great, super nice, and beautiful, have asked me out and I turned all of them down, I even didn’t go to high school prom a year ago after being asked by three girls. Many of the girls were girls that I would have killed for before I met the girl of my dreams. The girl I love is not the prettiest girl by far, I see prettier girls every other day. However, when I see her smile, it's like it's impossible for me to not smile back, it's like she is injecting me with happiness virus every time she is around me. At 19 years of age, I know I am not the most experienced person ever. However, I've had my petty crushes and loves before, and I know this is like nothing compared to that. I used to think of the world in sadistic and purely biological terms, everyone wants and money, everyone is selfish, everyone is doing something to increase the chance of ping on their genetic structure, order and sequence of nucleic acids. I used to hide behind my mask of super friendliness and stream of genuine-looking fake smiles. However, just knowing her made me have such a positive outlook on the world. After just knowing her, I smile genuinely, and my niceness comes from my heart, not from my desire to gain an upper social standing by portraying myself as a "great" person. I've been told to just move on and date other girls, and that actually can help me get the girl of my dreams. Even if I can force myself to do it, it seems so wrong to other girls because it would be like using them to fill the void in my mind, I feel like I would break someone’s heart by doing that, I don’t think I can put someone else through what I’m experiencing. The reason I’m not making a move is again, although she thinks of me as funny, nice, and great, she does not think of me as any more. Also, her current boyfriend has such great character, and I see how great of a couple they make. I know she can easily get a guy better than me in a snap of a finger, but I also know she will never be unhappy with me. I don’t want to force her to like me though when she has other such great guys. Urrg, what should I do, date other girls? I will still treat them really well, and I could love them, but never ever to this extent. Whoa what a long rant, haha. Well, if you’re currently reading this, thanks for making it through a long rant of lovesick teenager :)