I had my ADHD diagnosis earlier this year at 51 years old.
I also scored highly for ASD but not pursuiing that diagnosis as my assessor said without the parental letters about my childhood it would be difficult.
My child has ASD (diagnosed) and that led me to pursue my own.
I am a successful middle-aged woman, BUT I have had YEARS to develop strategies.
People say oh but you are on time, you hit your deadlines, you hold a job. What they don't see is the 5 alarms for each stage of leaving the house, the frantic procrastination before the deadlines and then fact I have been in the same job for 20+ years having built a series of accommodations and strategies even before diagnosis.
Peri-menopause actually exacerbates ADHD symptoms and that has made me get to a point where I was floundering and my strategies weren't working.
My ADHD diagnosis helped me be kinder to myself. not as an excuse as I am still fiercly independent but in a way that it's ok to slow down a bit.
I was on a waiting list for 3 years, it wasn't 'handed in' to be trendy.
ALso I tried meds - meds don't work for me. The stimulants left me with insane insomnia - i should have known as I can't drink energy drinks either - and the Non-Stimulants were working a bit but gave me gastrointestinal problems and the side effects were too much for the small benefits i got.
how you can help? i don't know? maybe making your friend aware of plans, not changing things last minute, giving plenty of notice, not feel targeted if they interrupt when you are talking or blurt out ends of sentences - honestly can't help it sometimes. and tasks have to either be done now or not-now and if a task is not-now we need reminders, calendar notices, anything to do them as the not-now time tends to vanish into oblivion.
Also we need things visible or we forget about them, in a cupboard? often out of mind. Things have to be in the same place, keys, phone, etc, or we forget. And so on...