@eviljackspicer It was mentioned in the previous chapters that her dad still holds a family reunion monthly with the mermaid side of the family; so definitely they did not split up.
And remember that these mermaids have a price to pay in order to get human legs and walk on land, so it won't be easy for the entire family to be together on land; much more with the case of the father who is human to stay under the sea. FeMC has sisters so there is a need for a guardian to be with them, which is their mother.
i always feel like in comic or mangas like these, where theres the childhood friend and a new friend made, it always seem that the main protagonist chooses the new friend instead of the childhood friend and i really hate that THE CHILDHOOD FRIEND GOTTA HAVE CHANCES TOO MAN