Sounds like her daughter might have had incorrect expectations for what it entails to call the police, though, unfortunately. The purpose and function of calling the police is generally to bring lawful force to bear against someone who has committed a crime. Any time you call the cops on somebody, it should be done with the expectation that they may be arrested and taken to jail, regardless of your intentions when making the call.
Police are not therapists and their job is not to resolve domestic disputes like a guidance counselor. While we might wish that this is what police would be, and while this is how excellent police might behave, in small-town settings, when you scale the system up to cities of millions, the function of police tends toward that of enforcing the law through use of force.
When you scale the police system up, it means the officers don't have a personal relationship with the people who call them, and they're going into a situation with no context. We can't fairly expect them to pass judgment on the spot about how a domestic dispute should be resolved when there's ambiguity and no law has obviously been broken - the courts are for handling nuanced, contextual situations like that where facts need to be determined, and fairness weighed. Anything less deprives one party of their rights.
Police also need to prioritize their time, because big cities are filled with constant real crime like theft, most of which is already never investigated due to lack of resources. In my mind, actual thefts (that deprive people of property and rights) are a substantially higher priority than resolving social disputes. Any time a police spends on social disputes is time taken away from fighting meaningful crimes that have obvious victims.
So from my perspective one should generally not expect the police to intervene for anything less than a law obviously being broken.
With this perspective in mind, police are a pretty "binary function". You call them because someone has broken the law and you need to bring society's force to bear against them, typically by giving them e.g. a lawful order to leave the premises of property you own, or by arresting them and taking them to jail. They are not "for" any other purpose. This is of course is not a defense of police taking people to jail for no reason in situations where they are called inappropriately, but I'm saying this to share my life experience in the hopes that it will set useful expectations for others: generally don't call police on someone unless you're willing to send them to jail.