I've found it's best just to ride out R/L crushes. I mean, realistically speaking, for those of us who fit the otaku mold, what are the odds that a crush would ever lead to anything worthwhile? I can't imagine many girls would stick around for very long after seeing the dakimakura, figures, and collection of Megami issues.
So, stick with the fictional characters. At least with them, it's no question as to whether they mind who you are -- they're categorically incapable of judging, being inanimate and all.