We poets would die of loneliness but for women, and we choose our men friends that we may have somebody to talk about women with. Letter to Olivia Shakespeare, 1936
Only be admonished by what you already see, not to strike leagues of friendship with cheap persons, where no friendship can be. Our impatience betrays us into rash and foolish alliances which no God attends.
Love between man and man is impossible because there must not be sexual intercourse and friendship between man and woman is impossible because there must be sexual intercourse.
The rule of friendship means there should be mutual sympathy between them, each supplying what the other lacks and trying to benefit the other, always using friendly and sincere words.