girl i love is going to date my best friend...need some help

Well, it all started out as a rumor...then a chat room...then boom all of the sudden theyre going on a date on saturday in 2 days...
Well i have no f*ing idea what to do...
should i let it be? Intervene? Ride it out? Be depressed for the rest of my life?
Ive been crying over this so much...
So tell me people...What the hell do i do?

Just stick it out. It's not like they won't break up...you can also use this away to get closer to your crush! :)
-Katie