... The female then often realizes that she has just lost her primary source of income, calls the police and tells them she doesn't want to press charges.
The incident report or the charges won't be 'cancelled', because if they were the male would be released from detention and the police would be called back within the hour.
One of the first things we were taught at the academy is that every domestic dispute is a potential homicide waiting to happen.
I agree with most of what you said but I disagree that the loss of income is necessarily the driving force behind a domestic abuse victim's recanting a report of abuse and returning to the abuser.
That is just one reason out of many.
Many victims fear retribution if they don't recant, and wisely so. An abuser often becomes more abusive (and dangerous) after a report of domestic violence has been made.
Many victims believe their abuser will change, or they find excuses for the abuse (e.g., too much alcohol, too tired, too hungry, their sports team lost a game).
Many victims believe they deserve the abusive treatment or it was their fault they were abused, not the fault of the abuser.
A lack of financial resources can certainly play a role - but it is not the only reason a victim recants.