I'm in love with my 14 year old childhood friend?

I'm 19 and it's obvious that it's illegal to be in a relationship with a 14 year old. For some odd reason this girl caught my interest 4 years ago. I've grown up with her and her brother as my best friends. She matured within a blink of an eye and had a lot of things in common with me. I loved listening to her tell me her secrets and problems, and how she would flirt with me. A year or two ago she actually started to gain feelings for me, but she was in a relationship. After that visit she totally just cut connections with me until she broke up with her bf. We reconnected soon after but every time I see her now it's like I can't stop being around her and I want to be with her, but due to the age difference it isnt possible. I decided I'd wait until she was of age, but it's killing me on the inside. Should I just let her go after loving her all this time? Should I move on due to me being and idiot? I don't know what to do.