Comments like this can cause a lot of confusion. In many opinion, in a lot of situation Comments like this and, "your my new best friend"i may throw you off and have you thinking "Im being friend zoned". But is that really what shes saying

Compare 2 different situations

1. You meet a girl at a party get her number. You talk to her for the next two weeks often initiating conversation often, not to much flirting, just a lot of chit chat and you get along. You start to show interest, and she brings up a comment "your my new best friend"

In this situation, it very possibly a LJBF comment. Probably just got fucked hard and not in the way you intended

Now how bout the same comment in this situation

2. You meet a girl at a party. At this party theres a lot of teasing and flirting. You two hardly know eachother and she says "Your my new best friend".

In this situation its very possibly NOT a LJBF comment, At least i dont think so. At this point, it seems like more like a girls version of indirect interest.

I am curious what you all think about that?

_________________
FAIL PROOF PICK UP LINE: excuse my, im sorry to bother you but my father beats me, can i have your number.

That sounds about right. See, often I think that can be an indicator of interest, because women are inherently more monogamous than men, so interest ties in naturally at least a little bit with relationship connection. It's the same reason we try to build comfort with a girl. So it's really all about context.