Assuming you're serious and can look past our interactions on other streams, I can offer you my 2 cents. If not, probably best not to read any further.
The tldr version is that the "why" is less important than what you are able to do about/learn from it, and the hardest part of that is recognizing and accepting what you do and do not have control over because it's unproductive and discouraging to waste time and energy on matters outside of your control.
Addressing specific things: it's not uncommon for friends grow apart. Neither they nor "everyone" hates you because--and I truly mean this in a supportive way--you're not worth the highly charged passion of hatred. I've fallen into the trap of believing everyone hated me, because I hated me and became so blinded by that hatred that it projected onto everything I saw. Eventually I realized that paradoxically it's an extremely arrogant sentiment for a self-loathing person to have. That was my experience, it may be way off base here.
The parental abuse thing I can't speak to...other than reiterating the need for people to know the relevant agencies in their area: police should have a child-services division and police can always be called to perform a "welfare check". As mandatory reporters if they encounter evidence of abuse, they're required to take action. (This may end you up in foster care, but it's probably better than an abusive home environment.) You could check this place out too https://www.stopitnow.org/about-us
Finally, when anyone gets to the end of their rope, the emergency room (or calling 911 for an ambulance trip to the ER) is a surefire ticket to medical intervention. Telling them you want to kill yourself triggers a period of involuntary psychiatric observation during which time you're evaluated and started on medication. It's expensive as f**k even with insurance, but you wouldn't be left holding the bag and unsupportive/abusive parents deserve to foot that bill.
Probably reading way too much into your post, but worth the effort in case I'm not.