I'll ignore, for a moment, the possible nature of the sins of Sodom and Gomorrah, and the problematics of Elie Wiesel (as enumerated by Norman Finkelstein), and those of gendered language, to quote the following passage, which, selfish as it in some ways may seem (though I do believe that genuine care of the self, which is not the same as selfishness, is the best and only way to care for others), is to me the best summary of why I do what I do given the personal toll it extracts, and given my pessimism about the possibility of change:
One of the Just Men came to Sodom, determined to save its inhabitants from sin and punishment. Night and day he walked the streets and markets preaching against greed and theft, falsehood an indifference. In the beginning, people listened and smiled ironically. Then they stopped listening: he no longer even amused them. The killers went on killing, the wise kept silent, as if there were no Just Man in their midst.
One day a child, moved by compassion for the unfortunate preacher, approached him with these words: 'Poor stranger. You shout, you expend yourself body and soul; don't you see that it is hopeless?'
'Yes, I see,' answered the Just Man.
'Then why do you go on?'
'I'll tell you why. In the beginning, I thought I could change man. Today, I know I cannot. If I still shout today, if I still scream, it is to prevent man from ultimately changing me.'
- Elie Wiesel, One Generation After.