She added: "They're both gentle people, not hysterical. They're always very affectionate and easy with each other."
The split was thought to be due to a turbulent few years.
Behind The Candelabra star Michael was diagnosed with throat cancer in 2010 while Welsh actress Catherine has suffered with bipolar II disorder for some time.
Michael Douglas and Catherine Zeta-Jones
Their marriage appeared to be firmly back on track as Michael and Catherine attended the opening night of drama play The Library at The Public Theater in April, before later continuing their return to the spotlight by supporting their friend Meryl Streep as she received the Monte Cristo award in recognition of her stellar career, at a ceremony in New York.
The Annual Chaplin Awards are the Film Society of Lincoln Center’s major fundraising event, helping to support the ongoing work in education, artist development, and cross-cultural film outreach.