https://en.wikipedia.org/wiki/Laura_Marx
Healthy in body and mind, I end my life before pitiless old age which has taken from me my pleasures and joys one after another; and which has been stripping me of my physical and mental powers, can paralyse my energy and break my will, making me a burden to myself and to others. For some years I had promised myself not to live beyond 70; and I fixed the exact year for my departure from life. I prepared the method for the execution of our resolution, it was a hypodermic of cyanide acid. I die with the supreme joy of knowing that at some future time, the cause to which I have been devoted for forty-five years will triumph. Long live Communism! Long Live the Second International.