Coping with death

Hello I have autistic and ADHD. I'm 29 and I live with my parents. I'm not as independent as I would like but I struggle in many ways like with cooking and finances, I'm ashamed to admit I don't think I could live on my own. My parents aren't just my parents they are my best friends and life without them is unimaginable. I lost my gran in 2020 and it affected me badly, my mental health turned bad and for a time I was detained in a mental health facility to keep me safe. Being detained wasn't a good experience and I still think it was perhaps an overreaction on the professional side of things.

However it has since made me wonder how I would cope if either of my parents died. I know they will as is natural of all living things but I wonder how those of you who are autistic have coped when people close to you have died? 

Based on my past experience I fear I won't cope well but I'm a bit older now and have gained many life lessons in that time. I know myself better and have my confirmed diagnosis's of autism and ADHD, both of which have brought me a lot of peace as they answered questions of why I never fitted in anywhere.

On the face of it I haven't changed much on the outside but on the inside I feel I can understand myself better than I did four years ago. I struggle with processing basic every day changes and for me death has proven to be the biggest change that has occurred in my life so far. I'm due to see a grief counsellor to help with my question here and to fully mourn my gran, whom I still miss now and have never really processed losing here.

I'm new here BTW. Nice to meet you.