Fashion is a way of not having to decide who you are. Style is deciding who you are and being able to perpetuate it.
The search for a life-style involves a journey to the interior. This is not altogether a pleasant experience, because you not only have to take stock of what you consider your assets but you also have to take a long look at what your friends call “the trouble with you.” Nevertheless, the journey is worth making.
The continued propinquity of another human being cramps the style after a time unless that person is somebody you think you love. Then the burden becomes intolerable at once.
Rome did not create a great empire by having meetings, they did it by killing all those who opposed them. If at first you don't succeed, failure may be your style.
Style, in the broadest sense of all, is consciousness. More specifically it is a consistent idiom arising spontaneously from the personality but deliberately maintained.