In love with a married man

Okay, I am not quite sure hoe it happen bc we literallt only talk as friends. I'm way to respectful and not that kind of female to ever cross any lines at all. I wouldn't want it done to me so I wouldn't do it. Here lately I've been finding myself misxing him, wanting to talk to him, getting that warm fuzzy feeling whem he talks to me amd everything. I'm pretty sure I've fallen in love with my bestfrieng which id married. Btw , before anyone judges know his wife is my good friend and knows wr are good friends as well. How can I possibly get over him and fall outta love with him with out losing my best friend. He doesnt know how I feel. Actuallt, no one knows how I feel so I'm all alone in this. Any advice?