Feeling Ancient at 17?

Im turning 17 after 8 days, ive been so sad about it. I know 17 is still young but like after my dad died at 15 i have been dissociated for 2 years, i didnt go out, make friends live anything. I was totally not really here. Turning 17 feels sooo scary and sudden. I never imagined ill be alive till this time and I have no one to talk to about this. I feel like i missed out on everything...everyone has hobbies, identity, character, friends something they love and do while im just...here. i wanted to learn drawing...i never did it because i was busy battling my mental health. I wanted to learn piano too but i never got to. I never took pictures with friends or did anything crazy or travel because i was always insecure about my body and always waited for the "right time". I feel so sad about what i lost. As i said im dissociated most of the time...like emotionally numb. I never feel happy, if i actually felt something it would be intense wave of sadness/ anxiety or just that crazy excitement that comes for an hour and then dissapears into a whole cry session. I know what is lost cant be regained...but does anyone have any solution to this sad feeling? About losing everything. I dont want to lose my last year as a teenager being sad and anxious about my past. I want to heal and live atleast 1 good year that i can tell my future children about.