Exactly manic. Mental illness in the worst cases can genuinely make it impossible to do anything at all, despite the sufferer's very best efforts, no matter how strong a person they are.
Someone saying they found the strength to carry on "because I had to" is very belittling towards those who, just like you, did their best - also "because they had to" - yet still lost their job, home etc. and are devastated. Talk about rubbing it in!
You're effectively saying that, unlike virtuous old you, they didn't try hard enough, or didn't care enough, which is not necessarily true. And that is a direct remnant of the outdated "pull yourself together" school of thought where mental illness is down to one's own fault, personal weakness, even immorality.
Maybe if they were 0.001 per cent less ill they'd be just the other side of the catastrophe line - who knows?
Most mental illness is not unbearably severe, long term and treatment-resistant, so of course most people somehow carry on, even when it's a huge struggle. But some don't, despite making just as much effort as the next person. Yes, we all prefer to feel we're in control of our lives and such devastating occurrences are normally unimaginable for nearly everyone. But there, but for the grace of God/serotonin/genetics/circumstances/chemistry/chance, go any of us.