I think that you are in the best position to decide how much to tell her. You should try your best to be analytical (if that is possible) about it.
Ask yourself what is the best/worst outcome from telling her. How much emotion do you really have invested in her (or she you, for that matter). Did she know you before? Is she invested with her perceptions of you before? What exactly do you want from her? Is it friendship, or something more?
Most things of worth in life are more complex and scary then things of little value. An old cliché comes to mind "Nothing ventured, nothing gained" that said please don't take any unnecessary risks. If you don't think there is much of a chance of a positive outcome then why bother.
I wish you the best of luck, with whatever you decide to do.
Best wishes,
Holly