>gather the courage to approach a girl
>she tells me to read her ring
>it's a heart with the encryption the says "Fuck off"
How do I recover?

If you had no good comeback in the moment, it's over. You just have to accept failure, because life continues whatever you do.
If you still have to see this person after this point for some reason, avoid them at all costs; if you physically cannot avoid them, do not acknowledge their existence.

>>33253303 (OP)
You go on to the next girl, reassured by the evidence that she wasn't rejecting YOU personally but came prepared to chase off anyone.