Aarkayne provided this link about Sadhna:
http://www.rediff.com/entertai/2002/feb/11dinesh.htm
Some excerpts:
Incidentally, her mother strongly disapproved of Sadhana's boyfriend, Nayyar, often asking her daughter to marry "someone like Rajendra Kumar". But in 1966, aided by her father, Sadhana tied the knot with R K Nayyar.
It was the best of times. It was the worst of times. A lingering thyroid problem aggravated, even affected, those much-admired eyes. Filmmakers turned their eyes toward fresher pastures. H S Rawail, who had once waited for months to ensure that Sadhana was part of Mere Mehboob, replaced her with Vyjayanthimala Bali in Sunghursh (opposite Dilip Kumar), while producer Pacchi chose budding star Rajshree to play Sadhana's role in Around The World (opposite Raj Kapoor).
A spunky Sadhana underwent a prolonged treatment at the Leigh clinic in Boston. She returned and threw a party for the who's who of the industry to announce that all was well with her. For a while it looked like she could pull it off. In 1969, two of her silver jubilees, Intequam and Ek Phool Do Mali, were released within a month of each other. Both were fuelled by Sadhana's star power.
But offers gradually diminished. Reluctant to essay character roles --- Raj Kapoor is said to have offered her the role of Rishi Kapoor's mother in Bobby --- Sadhana finally accepted the transient nature of stardom gracefully and eased out after Geeta Mera Naam (1974).
Then, after two decades of a tempestuous marriage that settled down to an even keel, husband R K Nayyar succumbed to an asthma attack. Sadhana, who had no children, was left alone. She keeps herself busy playing cards with friends at Mumbai's Otters Club, watching television and gardening. In keeping with her enigmatic image, she adamantly refuses to let herself be photographed in public.
She once told me, "I am the kind of person who loves being by myself. I do have regrets --- losing my baby was one of them --- but no rancour. I don't hanker for the spotlight. I want my fans to remember me as the Sadhana of Love In Simla, Mere Mehboob, Woh Kaun Thi and Arzoo."