The Packed To The Rafters star says her condition became so overwhelming she considered admitting herself to hospital.
“I couldn’t talk about it because I didn’t know what was happening to me,” she told The Herald Sun.
“I contemplated hospitalisation, but I didn’t want people to find out.
“I remember lying in bed and feeling like the walls were caving in. I felt like I was in the bottom of a pit. Every time I tried to claw my way out, I’d slip back down.”
Gibney, 49, says she suffered a major breakdown after a promotional tour for the film Halifax f.p, when she was 30.
She was in London at the time and took five Valium before boarding the plane home.
“I’m lucky. I’m through it,” she added, “but it doesn’t mean I don’t have down days. I just know how to deal with it now.”
For six months she saw a psychiatrist twice a week, continuing to make weekly visits for the year and a half after.
Gibney, who has a 10-year-old son with her production designer husband Richard Bell, next stars in the Seven crime telemovie The Killing Field, which will premiere shortly.
This article first appeared on News on 21 April, 2014.