The phrase "Old Lady", to refer to girlfriend, wife, or mother, very much appears to have entered the hippie language through Spanish. The male counterpart, "Old Man", for boyfriend, husband, or father, is in considerably less use in Spanish, so this can be said to have been comparatively more popularized by hippie culture. This is in line with the hippie culture's ideal of gender equality, which because Rome is not built in a day, was quite obviously imperfectly realized, taken as a whole.
The term was often employed with the somewhat curious usage of "THE old man" as well as "my old man", reminiscent of "the parental units".
The usage for lover is, at baseline, a term of endearment. However, its base words can carry negative meanings in mainstream culture. The user's mood would be the determining factor if a derogatory meaning was intended.
The usage for parent was a pretty bold statement in the "Father Knows Best" culture the 1960s was attempting to transcend. Users might well be making a statement against the authority invested in parenthood, and less at pains to avoid the negative meaning of the phrases' roots in the mainstream language.
The use in Spanish for the female version extends far beyond the hippie usage, however, reaching many of the same cultural expectations of aged women, and in particular old unmarried women, as in mainstream European/white culture.
The "single woman" aspect appears to also be extended as far as the concept of a "kept woman" or mistress (even if this is merely bragging on the part of the user, and even if the user is bragging about something the listener does not aspire to:)
- "In Spanish means old maid or older single woman. In Chicano Slang it is mostly a derogatory term meaning older woman. Also means a tried woman, as in having been through the trials of life and living. Can also mean an older woman of the barrio or older chola."
- "Meant to describe a girlfriend that has stayed by her boyfriend's side through difficult times, with an affectionate undertone. Also, to describe in light, derogatory (sometimes affectionate) terms a tried or worn woman no matter the age, identifying her presumed life experience."
- "When the older cholos referred to their girlfriends, they meant that they've been hanging around for a while. Better translated as 'old lady' as in 'I'm a hang with my old-lady today.' El chango is hanging with his ruca and his kids at the car show.
- "El morro se agarro una bien ruca! (The youngster got himself an older/worn woman!)"
- "She's been smoking since she was a kid, she's only 19 pero ya esta bien ruca. (but she's already old)"
Because so much of hippie culture came from black culture, it is possible this was the main or partial avenue. "Biddy" or biddie for cute young girl or small old woman is a black slang term, probably a revival of the 19th Century revival (indentured Irish domestic servant) of the 18th C English term meaning 'woman'. Interestingly, the name biddy came from "chicken", much as the later hippie term "chick". Word-detective imagines the calling of chickens as the origin, but women "bustling" in the extravagant bustles and sleeves of contemporary dress may also have suggested an image of a chicken. Biddy's use might preclude the use of Old Lady, or they might have been both used.