K.B.
I have ADHD, and almost 28... I have issues not completing things and for both work and family I know ALOT of people are counting on me to get things done SO I had to step it up. I have 2 celanders & to do lists, one is on the wall at home another in my purse. If I am out and about or at work and someone ask if I could do such and such by this date I write it down right away, then I transfer so they are identical. This helps me remember what I am doing when BUT it also helps me in seeing how busy or free I am so I can say yes or no to something.
This family member has to want to change first but if he wants to there are tons of great books to help ADHD adults to get organied. Organization is key as well as reminders (I put post-it notes EVERYWHERE to remind me of the things I MUST do and put the date when it needs to be done with). My husband smiles/laughs at all the post-it notes and how addicted I am to them but I need them otherwise I would let so many people down.
There is not much you can do unless he askes for some ideas on how to get things done... His wife can have more say and help him with keeping to do lists or going through a calendar each week asking him what he will be doing and if he needs any help with the stuff.
I do not take meds but at least for now I have my ADHD undercontrol enough to function without it... BUT my doctor has told me that with age it will get worse and might need meds (they really do make a differance I took them in high school and part of college). With age ADHD in adults seem to trigger memory loss/forgetfullness much quicker then an adult without ADHD.
Also the stress is killer for someone with ADHD, not completing something, lost of trust with family & at work add even more stress which will trigger even more of the ADHD symptoms and it really snowballs from that and is really hard to get out of without ALOT of help and maybe even meds!
Some books that have helped me:
Stress Can Really Get on Your Nerves! by Trevor Romain & Elizabeth Verdick (this is geared towards young adults but find it very helpful even if not in school any more)
Survivor Personality by Al Siebert
Being the Best by Denis Waitley
Time Management for Unmanageable People by Ann McGee Cooper
You Don't Outgrow It by Marnell L. Hayes, Ed.D
Succeeding Against the Odds: Strategies and Insights from the Learning Disabled by Sally L. Smith
There are many more books out there that are helpful these are just a few that I have the names of.
Support groups are also helpful but I have not gone to one, due to having my ADHD undercontrol and not search one out.