As Marcus Aurelius once wrote, all men suffer, but not all men pity themselves. Somewhat tangentially: Thomas Aquinas once wrote that if we experience a loss, we may allow ourselves to grieve for a while, and then stop. The danger of sadness is that we may indulge it indefinitely and sink into despair.

A person who wallows in such despair and self-pity would be well served by considering whether he is poisoned by envy, perhaps the envy of egalitarianism. To paraphrase Chesterton, at least the aristocrats of old had the satisfaction of feeling superior than others. The egalitarian man cuts down all those he fears are better than he is (typically by denying the qualities of others)!

The majority of our suffering, especially the spiritual and psychological variety, is our own doing. There are plenty of people born with all sorts of conditions who live happy lives because they've accepted the immutable and made the best of the cards they were dealt. If self-pity deserves anything, it is not compassion, but contempt.