Best Friend Code, Part One

When you and another person agree to be "Best Friends" there are a few terms and conditions which you must be ready, willing and able to fulfill as said " Best Friend", henceforth referred to simply as "BF". From this point onward the two (or more) parties agree that you will maintain and uphold certain responsibilities. When one or more of the parties terminates the BF agreement, the terms of the friendship must still be upheld even after the date of termination, unless there's some law/moral/good reason for not doing it (explained at a later date).

...but really, you don't use information about your former BF (fBF) against them unless it is to genuinely help them.

Example:

The partner of your fBF asks you questions about your fBF. The partner has absolutely no reason, no right, and frankly, I'm a bit upset that the partner was so callous to think that I'd do that to my fBF. That's not how I live my life.

I responded with a number of messages further detailing the above paragraph to the partner of my fBF. I told the partner that I was no longer in contact with my fBF and that no further contact was necessary from this point forward. 

Take the high ground. Think about how you would want to be treated. Live accordingly.