While Katerina is making this disturbance, people are short with her. The people were very nasty while in present day, i believe people would be more empathetic and understanding to her situation.
Doumia pities him, and promises not to leave him.
She acts very self righteous, saying that she is not a sinner and therefore has no need for him.
Yes they did have an obligation. Churches, even present day, should pray for the sick. Either for them to get healed or to be sent to heaven.
I believe that she was being over dramatic.
He gives Katerina and her kids some money
He reveals his admiration for Dounia, and that he finds Raskolnikov intriguing and likes watching what he does.