"So, even though this movie is probably for the Julie and Julia audience, young people can relate to the idea of being exhausted in a relationship," says Streep.
Directed by David Frankel who last worked with Streep in The Devil Wears Prada, it's her first film since her Oscar-winning portrayal of Margaret Thatcher in The Iron Lady. Promoting this film - and having been married to sculptor Don Gummer for 34 years - means the the talk inevitably turns to what advice she might have given her own married life.
"My opinion is to stay alert and alive to each other. Speak and be heard, break patterns and don't become complacent." she says. "It can be easy to fall asleep in a relationship and take the other person for granted."
But at the same time Streep says she's "no Dr Ruth. I don't make prescriptions. I'm not an expert."
However, she recalls her mother's words when she married Gummer over three decades ago. "My mother told me, 'Never go upstairs without taking something that needs to go up there'," she laughs.
And saying the movie is about baby boomers rediscovering a sex life is something of a misnomer, she says.
"In talking about sex we're speaking about our most vulnerable self - our needs, our insecurities and our nakedness, literally. We're talking about what we yearn for and what you never stop hoping for."
Now 63 and a three-time Oscar winner (from 17 nominations), how does she look back on her career?
"It's a miracle that opportunities keep coming. It's different now than it used to be in the history of movies. In the past, women my age were absolutely one foot in the old age home.
"In terms of the work, it gets richer as you get older and you have more to pull from because you have more stuff inside. Your imagination does not stop firing and you have a bank of experience to apply.
"There's also an appreciation for how little time you have to tell your stories and you want to pour everything into it."
Speaking of ageing, time has evidently been kind to Streep, who looks many years younger than her age, without any apparent plastic surgery.
"Well, it's been pretty good so far, except for the knees," she laughs.
Turning serious for a moment, she says, "As I lose friends, you can't help but mark the passage of time and understand that things are changing.
"You have a deeper appreciation of the finite number of years you have and you want to say something important in that time. You want to make it count and you want to help and make people happy. You want to be there for all of it."
"Somebody said to me that the secret of life is enjoying the passage of time. I think that's where I am," she says.
"I'm aware of how lucky I am to be living right now."
When: Opens at cinemas on Thursday.
-AAP
