quote: she was happily married for over 50 years

Not really. Well SHE may have been happy for all 50 years, but she drove her husband Frank O'Connor to alcoholism with her affair with Nathaniel Branden. The affair also also caused Branden's divorce from his wife Barbara. Branden and Rand, according to Barbara, literally followed a page out of her novels, bluntly telling Frank and Barbara that they intended to have an affair because it was the right and moral thing to do to be their selfish selves per her philosophy.

Rand eventually excommunicated Branden from her circle when she found out he had been sleeping with other young Objectivist acolytes.

Barbara Branden wrote a book about this time period-The Passion of Ayn Rand, which presented her version of Branden's relationship with Rand and the bitter breakup. The book was made into a motion picture in 1999 of the same title, starring Helen Mirren as Rand, Peter Fonda as Frank, Eric Stoltz as Branden and Julie Delpy as Barbara.