Secrets and the Whores that Tell Them

I prefer not to tell anyone my secrets.  Whenever I do, it just so happens that that particular secret leaks out to the world.  Maybe it's the people that I choose to tell.  Maybe what I tell them is just so juicy that it cannot be kept inside and the world must know of the evils that I have done! Meh.  Not so much on that part.

To preface my frustration and my anger, I must tell you this little diddy.  My youngest "full-blooded" sister (let us call her B) is a skanky ho.  She lost her virginity last year to an ex and has slept with at least two other guys (that I know of).  That part only makes her a slight ho.  How did she make the descent to skanky ho?  By breaking a 'sister secret' to further her own agenda. 

Definition of a sister secret:  I have three younger sisters. The real youngest is my half sister and is too young to yet be included in the sister secret circle. Eventually, when she starts her period or something, we'll include her.  So, the other two sisters and I have made a pact that when we need to get something off of our shoulders, we can tell each other without fear that that piece of information will be shared with anyone else.  ANYONE.  Spouses, mother, father, etc.

B seems to think that this rule no longer applies to her.  I told her a sister secret, one that never should have left me lips, but seemed to roll effortlesslly off of hers.
No, I did not cheat on my husband. I never will, nor could I. 

Anyway, when she came under fire for sneaking out of the house to meet her boyfriend, she told the sister secret.  "Megan snuck out of our old house to meet her boyfriend and Sarah slept with, like, four guys in high school!"

What.  the.  Fuck. 

She was trying to justify her own stupid behavior with our stupid behavior!  Let me know if I'm not making sense, or if she was right in justifying herself in this manner.  However, I cannot.  I told her that secret in confidence, when she needed advice.  Yes, I was borderline retarded for confiding this in her.  She's not a good secret keeper.  She sucks.  She's a bitch.  And I hate that she thinks of only herself when she comes under fire. 

I'm going to punch her in the taco and then give her a shirt that says "Shut your whore mouth", c/o Aunt Becky.