“A woman had to choose her own particular unhappiness carefully. That was the only happiness in life: to choose the best unhappiness. An unwise move, good God, you could squander everything.”

Where the Blue Begins (1922)

"Prince Charles discusses marriage", The Times, 27 June 1969, p. 10
Asked about "the lady the Prince should marry" in a joint televised interview with BBC and ITN broadcast on 26 June 1969.
1960s
Context: You have got to choose somebody very carefully who could fulfill this particular role, because people like you, perhaps, would expect quite a lot from somebody like that and it has got to be somebody pretty special.

Original: (it) È accontentandosi che si sceglie di vivere infelici.​
Source: prevale.net

.
The Story of My Life (trans. Sartarelli/Hawkes 2001), Preface, p. 10
Referenced
Variant: [H]appy or miserable, life is the only blessing which man possesses[. ]

AP reports, (1 November 1963)
Context: I've had a lot of unhappiness in my life — and a lot of happiness. Who doesn't? Maybe I've learned enough to be able to guide my daughters.

Все счастливые семьи похожи друг на друга, каждая несчастливая семья несчастлива по-своему.
Pt. I, ch. 1
Variant translations: Happy families are all alike; every unhappy family is unhappy in its own way.
All happy families resemble one another; every unhappy family is unhappy in its own way.
Variant: Happy families are all alike; every unhappy family is unhappy in its own way.
Source: Anna Karenina (1875–1877; 1878)