I really need help mentally.

please help 

I've been struggling recently and just need to get this out into the world because I feel so alone. Ever since my nudes got leaked I've felt so violated by not only myself but by everyone. I've convinced myself I was useless and only on this earth as a source of entertainment for others. it's always been that way tho. then over the summer I was sexually assaulted by someone I thought I could trust. I told one of my really close friends after I convinced myself it was love and she said it was assault. I've been disgusted with myself... I don't know how I can keep going. I feel like a fraud yet it seems that is the only way I can go on, I act so happy and confident and carefree-like nothing bothers me... but that is not how I feel, because of that nobody validates my feelings, they never have and they never will. I say I feel like killing myself and my friends think I'm joking, ive cried out for help so many times but nobody will see that. It feels like I'm not allowed to have feelings. anyways, I digress. after my assault I started smoking a lot with my best friend who is an addict. at first it was just something to do for fun but then it developed into something more. after I got a dab pen I was taking strong hits like every 1 1/2 hours. I felt out of control without it. I was smoking weed in the bathroom with my friend from school atleast 3 times a day and skipping class a lot.( I go to a really small catholic all girls school so its hard to get away with things).  then I almost got caught, so I flushed my 5 carts and 2 batterys down the toilet, now I deeply regret that as weed was the only thing keeping me going.  I have diagnosed ADHD and OCD which I have been diagnosed with since I was 7 so ive always felt out of place and insecure because of it. at first I felt really good about my looks since I was basically the beauty standard (tall for my age, blonde, blue eyes, skinny) then puberty hit my like a rock. although im still 5'4, 125 pounds and 15 (please don't comment on my weight atm) I don't recognize myself any more. everything feels like a dream and I don't know what's real or not. I stopped doing drugs/drinking like 3 months ago so idk why I'm still derealizing (idk if that's the right termology for how I'm feeling) I really looked at myself for the first time in years yesterday and it felt like I was woken up. I couldn't stop crying. I realized what had happened. I'm not 12 I'm 15 now, I'm not 300 pounds im 125, I have a car, I have a life, things matter, life is real, im not just in a dream like the things I do matter and this is causing me so much stress, I also have diagnosed depression and I realized that wanting to kys everyday isn't normal. I don't know how to feel about me "waking up" like I feel alive for the first time in a long time but now things actually matter and that's making me feel too much, I see every thing now. I still feel like a slave of society however I'm now aware. I feel like everything is too much and I just want to die. I'm still insecure and depressed but now im realizing that that is actually real. I don't know why ive just shut down since I was 12 because like my whole life feels like a blur I can't really remember much of anything that happened to me really before like a year ago. is this normal? please help I'm spiraling.