at the very beginning - i'm 17 years old male and english isn't my native language so i'm sorry if i made any mistakes.

since november 2015 to december 2016 i had the best year of my life and since then i don't feel like i'm alive anymore. basically i created myself from a scratch back then - i chose the way i want to act, my priorities and i made 2 new friends while cutting all the friendships i had before. i was fit, the best student in my school and i was able to FEEL. everything in my life seem new and i saw life in general as a wonderful adventure with a huge amount of possibilities. i had hobbies and i was always doing something, i loved science and learning. but at the same time i was battling some kind of eating disorder - i was really afraid of unhealthy foods and i was "adddicted" to exercising (i was exercising at least for 3 hours a day but during summer it was sometimes more that 5 hours...).
after december 2016 i gained a lof of weight, almost 20kgs. i was still slim because before weight gain i was definitely too skinny but even though when i got bigger i felt disgusting. since then i stopped living. for most days i was just laying in bed and watching tv series, occasionally going to school. i barely passed that year. from the best in school i became the worst in my class. i changed my behaviour, lost those 2 friendships because i was too tired to keep them. basically i stopped existing. i was just laying in my bed eating untill september 2018 came. i went to a new school (learing system in my country is a bit different), started taking antidepressants. i stopped self harming and drinking, i really wanted to move on with my life and start a new chapter but it seems impossible. I CAN'T STOP MISSING THE PAST. my biggest wish is just to time travel and go through the best year of my life again. i miss those 2 people so bad, honestly the best friendships in my life and no one even is half good as them. i don't feel like myself, i'm a whole different person. i don't study well anymore, i just don't see a point. i don't have a single person to talk to. i'm just constantly missing the past, reading old messages, listening to old songs, going through the memories in my head. i know it's impossible to recreate it but that's all my heart wants. my head says i need to start the new chapter but i can't.
the worst thing is that i don't feel anything. every single moment is so dull like i'm always behing some curtain. i'm not depressed anymore for sure. i'm just so empty... life seems so shallow, people seem shallow. everything lacks the deph that i saw before. i don't have any hobbies, plans, dreams. i don't have anything to do in my free time. each month reminds me of the same month in the november2015-december2016 peroid and i just try to feel like it's not 2019 but the time before to go through the memories in my head of the things i used to do at the same time a few years ago.
at the time i don't have the possibility to go to the therapy because i'm underage and my parents don't approve it. i'm losing years of my life and i feel so helpless.... i changed so much and i hate it....