i've often tried to explain why i'm friend-repulsed – what is so uniquely distressing about friendship to me, compared to other interpersonal bonds – so here's one part of it.
friendships feel distinct from other types of relationships in that they usually start without any agreements, and can be entered into without even realizing. growing up, this was frightening to me; to hear a teacher declare we had to be friends with every student in the classroom, or to be called friends with someone i was just polite or kind to. when i did see models of “people asking if they can be your friend”, it was in children's books about how rejecting them makes you a bully. there was, and is, no escape. to suddenly hear that someone considered me a friend, and that i would be an evil oath-breaker if i left them or failed to be a “good friend” or sat there and did nothing at all, was bone-chilling. i made no oath!
i'm a scrupulous person, and i was even worse as a kid, so my society's friendship norms hurt me a lot. i didn't have any cultural example of how to say “no” to “do you want to be my friend?”, no script to turn down a kind and well-intentioned request for friendship, no means of egress that didn't make me a villain. i would regularly end up in – what seemed to me – servitude to some other child, not sure how i got there but unable to leave until they lost interest in me. i felt bent to the will of one person after the other, each one oblivious to how i felt their every friendly action as suffocating, consuming, as knives carving me into an empty statue who would do what they wanted. i was given no model for negotiating a friendship contract, but always reminded that there was a contract, one that i could not see or understand or alter.
...of course, there are always unspoken rules in social interaction, and culturally-approved coercion, and awful norms around consent. but there's something about how harmless friendship is seen as, and how socially discouraged it is to deny it, that hurt me a lot. i didn't have a drive towards friendships, so my friends were decided by whichever child was pushy and domineering enough, and i assumed that was just how things worked. i never even noticed when my friends actually treated me unfairly, because all of it hurt so much that i couldn't tell the difference. until i found the apl community, i couldn't find the language or ideas to even begin to think about it!
i think in most possible worlds, i would still be aplatonic. but it's this – my own experience of friendship as an inescapable torment, tearing chunks out of myself and offering them to whoever was strong enough, while the adults around me called me “such a good friend” – that made me friend-repulsed.