Sharon Tate's quote suggests that she believes her life has been predetermined by a greater power. She might feel that her life has actually been predetermined by fate, which she has no control over the occasions that have happened in her life. This could be translated as a sign of resignation, as if she has actually accepted that her life is out of her control. Alternatively, it might be interpreted as an indication of faith, as if she thinks that her life is in the hands of a greater power which everything will work out in the end. No matter the interpretation, it is clear that Sharon Tate thinks that her life has actually been decided by fate.
"There is a tide in the affairs of men, Which taken at the flood, leads on to fortune. Omitted, all the voyage of their life is bound in shallows and in miseries. On such a full sea are we now afloat. And we must take the current when it serves, or lose our ventures"