im so sorry that this is happening to you. by the sounds of it your mother has her own mental issues that she is dealing with because her behaviour does not portray that of a rational parent; keep this in consideration. by no means am i saying to completely let go of everything she has done to you, but think of it like your mother is somebody who is mentally unstable and unable to control her behaviour towards you because of personal issues inside HERSELF. please dont blame yourself for the way she treats you because IT IS NOT YOUR FAULT.
If you are looking for opinions, i personally think you need to get as far away from your mother as possible. she is not good for you. how can u expect to be happy and secure in yourself when she is constantly bringing you down because of her own problems? because she is your mother, theres no doubt that you will feel guilt towards the idea of leaving (i believe this is innate) but i say do it! youre 18 and about to begin the rest of your life! would you rather stay at home with an abusive mother or far away in a more positive environment and taking in what the world has to offer you.
I've had similar issues with my mother and found out that it was her own personal insecurities all along. she got help and counselling and our relationship is very strong now. similarly for you, maybe the idea of leaving permanently is not the solution but you definitely deserve a break.
Please stop hurting yourself!! Please! If you ever need anyone to talk to, im going to uni soon too, you can email me: [[personal details removed] and keep us posted