She is the embodiment of your "ideal" ...of everything you want. You probably can't let her go, because she symbolizes everything you want in life, but can't have.

You feel safe in knowing that you will never have what you want (or turned down because of it), instead of going after a relationship with someone in your life. You could be disappointed in real life while your celebrity crush is a fantasy.

Giving up the "crush" is equivalent to giving up your dreams. Although, you know rationally that she is a false ideal, your feelings feel very real, and knowing that you can never have those ideals (her) thwarted makes you feel safe in the illusion.

My best advice is try to figure out/define which traits appeal to you... maybe, ask yourself why those specific attributes apeal to you... and then, look around you.

There are real people surrounding you, real people (women). Women who possess those traits. There is no reason why you can't/won't be happy with someone who is available and real... and who wants you back. Don't be afraid of the possible.

However, I don't know you and that is just my best guess. I know how painful it can be to feel that lonely, but please, feel free to ignore me. I hope you find answers soon.