Op - depression/mental illness IS helped by good physical self care too, lots of evidence/research on this. It's why I'm always trying to improve my diet, sleep etc
Also I agree it's not acceptable when mh is an issue to not try and improve matters. As I say I've suffered for many years but refuse to give up! I've tried different meds, therapies, complementary therapies, self care... some of it has/does help, some hasn't or has even made me worse but I don't think not even trying is acceptable especially where it's impacting others daily.
Unfortunately the nhs is so underfunded and under resources especially in mh that "the squeaky wheel gets most oil" you have to be vocal.
I'm also physically disabled, again I could give in and do very little, have people doing stuff for me but I pace myself, find workarounds, use equipment that makes certain tasks easier/possible! Eg I've had fun and games this weekend cos I ordered ready peeled potatoes to try for the first time (I'm no longer safe peeling myself) but it's led to me having dishes I've not had for years and I think I now have a grip on using them such that they'll be a useful addition to my repertoire.
lots saying "it can't just be a weekend thing if a genuine illness" it really can. People can push themselves to keep going in the week, "working on adrenaline", using all their energy to keep working, but then when not at work the adrenaline (and other hormones and chemicals) drop and they slump. Lots of people with autoimmune, chronic pain, mh conditions can experience this.
I have severe ocd, I'd be "masking" throughout the week to manage taking dd to school/childcare/clubs, to work (without colleagues seeing ocd behaviours) when I was working and then come the Friday evening it'd go into overdrive! Cue sore bleeding hands and shakes on a sat morning and my being unable to cope with any plans for that part of the week I had to work around that so that sat mornings were a "calm" time/activity. Thank fuck for kids cheap sat movie clubs in the cinemas at this time!
I've a few friends with various conditions - fibro, ME, MS, depression... who push on during work hours then days off basically collapse! One (with fibro) basically every Tuesday she Parps the kids to school, gets home, sleeps, then sets alarm to get up for picking kids up from school and does the little housework she does that day after they're home from school. Her other day off is a Sunday and she doesn't get to sleep that day as kids home and so that's when her and kids get bulk of housework done together (lone parent mum).
Lots of disabled people plan "downtime" into their weeks but they also meet their family responsibilities.
If he does have a medical condition then with a dx it becomes a bit easier to learn how to manage the condition and how to pace themselves.