You can choose your friends but not your family, that is what "they"say. To some extent this may hold true because you cannot choose your blood relations.
However, sometimes you find yourself surrounded by a man who loves you more than the universe should allow and two more who would lay their lives down to save yours as surely as if you were their sister. They do it unconditionally and they do it willfully and willingly and without hesitation.
So maybe "they" are right, it isn't our choice at all.