Welcome to the forum.
Are you getting any outside help?
My son was brain damaged when he was born, in all that time I never had as much as a week off. After caring non stop for 16 years I was so ill that he moved into boarding school. My health never fully recovered.
Now 42, he lives in his own flat with carer support.
So many people assume that a "carer" is looking after someone frail and elderly.
In my area they have Carers Meetings, but I was usually the youngest by about 30 years!
Caring for someone under pension age brings different challenges. Do you ever get a break?