*sighs* This is a tough one because I barely have that many trusted friends to begin with... Trusted acquaintances are a dime a dozen from my perspective, but I honestly only have one trusted friend and not just because we could literally talk about anything without feeling like we're "lying" to one another...
Anyway, back when I was in high school, I did hang out with a high school drug dealer... He once asked me and my one of my friends if he could borrow some games of ours... Pokemon Emerald and Mario Galaxy, to be more precised... He never brought them back, blamed it on his "girlfriend" smashing them up, and then got arrested for drug possession and distribution "coincidentally" on the same day he said he was going to buy us new copies of the games he borrowed... And that's why I only have one trusted friend...
Other than that... uh... I can't think of any other dealbreakers other than that whole "borrow and never give back" thing... That seems to be the only one so far that I would personally call a "dealbreaker"...
Anyway, back when I was in high school, I did hang out with a high school drug dealer... He once asked me and my one of my friends if he could borrow some games of ours... Pokemon Emerald and Mario Galaxy, to be more precised... He never brought them back, blamed it on his "girlfriend" smashing them up, and then got arrested for drug possession and distribution "coincidentally" on the same day he said he was going to buy us new copies of the games he borrowed... And that's why I only have one trusted friend...
Other than that... uh... I can't think of any other dealbreakers other than that whole "borrow and never give back" thing... That seems to be the only one so far that I would personally call a "dealbreaker"...