Trust issues

[Rmelnikas]

So recently I told of of my closest friends some stuff that was troubled in my life, I also told them about some stuff that happend with a girl and I was hoping that the person would hear what I was saying but not tell anyone but then tonight my sister comes home and tells me says to me the exact things I told my best friend.
So I confronted my best friend about telling my sis and the reply that I got was that she didn't tell my sister.
My problem is if I can actually trust this friend or is she just going to tell my sister everything I tell her?

[Kaius]

Are you positive it came from your best friend? Or could it have come from someone else?

[Skatergirl]

Are you positive it came from your best friend? Or could it have come from someone else?
^This

Also I wouldn't tell your friend anything until it's sorted out?

[Rmelnikas]

Well I not 100% sure, but People told me things I only told her so in my mind she must have told.
She my best friend and we are really close and I dont want to lose that. I hope she didn't tell but how would I find out without destroying our friendship.

[Skatergirl]

If you don't want to lose your friend, you're going to have to believe that she didn't tell. If it was her, then it wasn't your fault of course. :/ You could always forgive her, and give her another chance to be trustworthy.
Lets just hope it wasn't her...