Martin Sheen on son Charlie's meltdown: "we were powerless to do much except pray"

The West Wing actor admits he did not see his son perform any of his live dates, but adds, "What he was going through at that time, we were powerless to do much. Except to pray for him and lift him up."

"You try to be as present as possible," he tells the new edition of Radio Times. "But you have to be aware of the circumstances. You have to be aware of many things that the public is not aware of.

"Only those of us that knew him understood what was going on. I'm talking about steroids, at that time. He was in a very desperate situation. And he was doing what he felt would get him out of it – going public. And it was very painful. No less painful for him."

Sheen himself has struggled with addiction – his heavy drinking led to a heart attack in 1977 on the Philippines set of Apocalypse Now. He's now been sober for almost 30 years, and says that Alcoholics Anonymous has helped teach him how to support his son. "You can assure them you're there and you love them, but you cannot effect change. That's your ego, for the most part. You pray for a moment of clarity, you trust in a higher power and you never, ever give up hope. Because that is a measure of despair."

After his seven years leading the cast of The West Wing as President Joshia Bartlet – a part that saw him win a Golden Globe and two Screen Actors Guild awards – Sheen took his next regular TV role in series two of Anger Management starring alongside Charlie. The series debuted in June 2012, just a year after his son's meltdown, and received largely negative reviews.

"Anger Management didn't set the bar that high," admits Sheen. "I was delighted to work with Charlie – I adore him, and he asked me to do it. But we all knew that it was pulled together very quickly to get Charlie [involved], rather than to have a more interesting theme. It was too surface."

The elder Sheen can now be seen in Netflix comedy Grace and Frankie, co-starring Jane Fonda, Lily Tomlin and Sam Waterson, and following two men in their 70s who leave their wives for each other. Sheen believes in gay marriage – "I am not against anybody expressing their love to anyone else; it's none of my business" – but says he did take issue with some of the scenes in his new sitcom, particularly one which sees a giant pink penis installed on his character Robert's lawn as a joke for the couple's bachelor party.

"I would not participate. Such vulgarity. And I told dear Marta [Kauffman], the writer, it's awful and it's a bad choice. I was honest with her, and I'm glad I was. She looked at me and said, 'Well that's your opinion.' And I said, 'Yes it is, and I'm not participating in that sequence'."

You can read the full interview with Martin Sheen in the new issue of Radio Times, on sale from Tuesday 19th May in shops and from newsstand for iPad and iPhone.