Thinking of Best friend turning yandere...
But honestly, they see how the other people around you are treating you. They have been your best friend for years now! Someone else comes along and tries to take their place next to you. The little pest is just using you!
Bestie makes it seem like the other person dropped you out of nowhere for no reason. Constantly threatening any newcomers that you bring up in casual conversation.
Oh! You... like someone? That's... good to know, no [redacted] I'm fine really! Bestie pointing out all the flaws in your relationship or crush anytime you ask for advice. Always telling you that a s/o would treat you better than they would. Even though they never could come close, you're my best friend after all.
Bestie coming over to your house to spend some time with you. Your family always want them over for the holidays. They take pride in getting on your families good graces. Their so called partner can't even greet the family properly... how pathetic.









