I don’t think that is good advice.
One should not contemplate the horrors of the Holocaust during an episode of depression. That’s...no.
To contemplate the indomitable spirit of those who survived - is uplifting.
The faith they had that helped them through the horrors while not succumbing to self pity is encouraging.
Perhaps I see the glass half full while you see it half empty.
Rarely when a person is depressed will the plight of others depress them more.