If any young Miss reads this autobiography and wants a little advice from a very old hand, I will say to her, when a man threatens to commit suicide after you have refused him, you may be quite sure he is a vain, petty fellow or a great goose; if you felt any doubts about your decision before, you need have none after this and under no circumstances must you give way. To marry a man out of pity is folly; and if you think you are going to influence the kind of fellow who has “never had a chance, poor devil,” you are profoundly mistaken. One can only influence the strong characters in life, not the weak; and it is the height of vanity to suppose that you can make an honest man of anyone.

Margot Asquith (1864-1945) British socialite, author, wit [Emma Margaret Asquith, Countess Oxford and Asquith; Margot Oxford; née Tennant]

Autobiography, Vol. 1, ch. 7 (1920)
    (Source)

In a similar vein, in More or Less about Myself, ch. 5 (1934) she wrote: "It is easier to influence strong than weak characters in life."