Yes. While the two had an on-again off-again relationship for many years, Al Pacino refused to marry Diane Keaton.
But that says more about Pacino than it does Keaton.
Even before her recent passing, Pacino has described this as one of the biggest mistakes of his life.
Sadly, his refusal came down to a dysfunctional childhood and a very difficult family life.
His parents divorced when he was only two and he was raised by his mother and maternal grandparents. His father moved away from New York City shortly afterward and had next to nothing to do with his son’s upbringing, settling in California.
Pacino then had an ugly falling out with his mother in his teens because of his choice to pursue a career in acting.
As a result of this fight, he moved out, or was kicked out, before age 18 and supported himself through a series of jobs while attending the High School for the Performing Arts.
His mother and grandfather subsequently both died by the time he was 22.
So not exactly a great childhood, and not exactly one where a young Pacino could place a lot of faith in relationships enduring.
At a guess, his lifelong commitment issues - now age 85 he’s still never married - can be traced to back to all these ugly events in his upbringing.
So despite being in a relationship with Keaton for many years, he never married her.
For her own part, Keaton never married either.
She had other high profile, tabloid fodder relationships throughout her life, particularly with Woody Allen and Warren Beatty, but remained single until her recent death.