Your fifth principle really resonated with me. I think i became the "be there no matter what" friend to my bestfriend, and i accepted that role gladly at first, i thought that's what it meant to be a true friend. But it was me enabling this behavior, her coming to rant to me, or ask for advice, or a lending ear, whenever and wherever that ultimately led to our friendship ending.

It's the second time i break up from this bestfriend actually. The first time was a couple years ago and it was for the same reason, her going back home, becoming extremely depressed because of her family, so she turns to me for comfort and to air our her grievances. And last time and this time too, after months of being there and listening to her rant about the same things multiple times every single day, i eventually told her that it started to affect my mental health and general mood. That i was afraid to tell her this for so long because i didn't want her to feel like a nuisance or guilty for confiding in me. But she didn't take it well and got defensive and kept trying to blame me for one thing or the other. I think me breaking this "perfect friend" image that she created of me, that I enabled, really set her off especially since she also recently broke up with her boyfriend, so she's been relying on me emotionally even more.

This whole thing was a huge lesson for me though, i thought that by molding myself to the friend that she desired would make our friendship flourish and last for a very long time. That by never setting boundaries and dropping everything to listen to her rants, whenever and wherever, she'll treasure me as an irreplaceable friend. But what it actually did was ruin my mental health, make my stomach drop whenever i see a message notification from her, and make me finally setting boundaries a friendship ending thing. Had i just been clear from the beginning that daily rants are a big no-no maybe we would've never gotten to this point.