Is it normal to be torn up with how my friend will never love me?

I've been in love with her for years. I know that she'll never feel the same way, but I keep carrying on this pointless hope because I don't know what else to do. Every time she touches or hugs me, I wish I could feel the warmth of love, but I know there's nothing. Every time I look deep into her eyes, I know she isn't as into it as I am. She smiles when she catches me staring, but I know she's only trying not to make me feel awkward. Every time she texts me just to chat, which is almost every day, I can't help but feel empty by how I'm just chatting with a friend instead of building a relationship. Just the other day, when she sent me a pic of her in a new flannel skirt she had just got and asked what I thought, I was honest and told her it's sexy. But I knew that when she responded with a winking smiley, she was only being polite to me overstepping my bounds with a rudely flirtatious response and trying not to make me feel weird. She told me if I liked that she had some other things I could see her try on, but I knew it's one of those weird things girls do where they offer something but get mad if you actually accept it and act like they think you hate them if you turn it down. So since I was trying to fix my mistake and be polite, I told her I was busy at the moment but I'd love to when I could if the offer still stood. She told me well if we were going to plan ahead like that, I should come over and tell her what I thought of her new lingerie in person. And it's things like that that tear me apart. Because she thinks we're just friends, she doesn't realize how much it hurts that her sexy apparel isn't for me. All telling her what looks good does is make her sexier for whoever she eventually does fall for. If we do that, I don't know if I'll be able to handle the longing. She said in the meantime, she could send me an email with some pics for me to look at when no one would interrupt me, and again, realizing her game and that I had to refuse in a clever way in order to avoid her hating me, I told her that would ruin the surprise and I'll enjoy it more if I see it for the first time when I'm there. She said see, that's why I'm the reason she hasn't dated in years. Really? Has my friendliness killed romance for her so much that now she can't be attracted to anyone? I'm ashamed. She doesn't want to hurt me, but she keeps tearing me apart.