I’ve seen firsthand how blaming outside circumstances for mental health can be damaging. Both for myself and others. It’s very tempting to blame lack of happiness on your job, where you live, your partner, or an upstairs neighbor who rearranges their entire apartment at 2am. In most cases (not all) these were misattributed.

Also I think your attitude is unnecessarily defeatist. So what are you suggesting instead, that rather than attempting to build healthy habits, depressed people should give up?