You are the dick keeping a friend in the friend zone.

Do the kind thing. End it. It will hurt like fuck, but the hurt will end. That's your only option.

If the crush were less developed, you'd have other options. But she's literally in love with you, living in hope for the "straight girls will like women once they get properly eaten out" mythology, which I (and a billion others) can tell you isn't true. And you know it. And she probably knows it too, she's just too in love to see it for what it is.

Sorry.

Keeping a friend who is in love with you is a SHITTY thing to do. You can pass off responsibility (well, she could stop hanging out with me) but in the end, you're the asshole. You keep seeing her, talking to her, talking her phone calls, KNOWING she wants you to love her and knowing you'll never feel that way. That makes you a prick. So stop doing it. Break it off, clean and hard and fast. Make it mean. God, even mean is kinder than living in hope. End it. Fucking end it.

You have to. You know this.

This isn't about gender or sexuality. There are same-sex/opposite-sex/who-gives-a-fuck attractions that settle into friendship. And that's groovy. And there are hard core crushes you need to do right by in stomping them out and being the bad guy. And being the bad guy means cutting contact, being a dick for (seemingly) no reason, and embracing the inner jerk you don't want to embrace. We ALLLLLL Fucking HATE THIS. All of us, man or woman, gay or straight, queer or not. It. just. sucks. But it is what you need to to actually be a friend when someone can't let go or move on. It is the sick and twisted kind thing.