Redeemer, by C.E. Murphy

Second paragraph of third chapter:

“He hit her,” Rosie told the police, “and came after me. I had no choice.”

A cheerful tale of a young woman, working in a Detroit factory at the end of the second world war, who discovers that she is the chosen Redeemer capable of ridding the world (or at least America) of the demon enemies of humanity, one exorcism at a time. She must also deal with friends, potential lovers and family, and their expectations, in particular choosing between Boring But Handsome Guy and Smart But Weedy Guy. The book is the first in a series, so that last question is unresolved, but I know which side my money is on. Good fun anyway. You can get it here.