Jessica Chastain fell into a spiralling depression while out of work.

The 37-year-old actress has spoken about the sadness she felt when she unexpectedly found herself unemployed.

The 'Zero Dark Thirty' star admitted that being selective about which films she appeared in ended up being detrimental to her health when she was left with no options.

In the November issue of Harper's Bazaar, she says: ''[Not working felt] a little bit like grief and I started to feel really negative about myself, down on who I am, and then I realised it's because I've had so much time away from me that I don't really know what I like to do any more.''

However, she said she is now feeling a lot more positive following her work on new movies, including Guillermo Del Toro's 'Crimson Peak' and crime drama 'A Most Violent Year'.

She explained: ''I'm out of it now but there was this feeling of being sad or depressed... wanting to go to another project.''

Despite her rediscovered optimism, the Golden Globe winner revealed she still feels self-conscious about her behaviour and image.

She added: ''Probably there are some people who feel great about themselves and don't second-guess anything they say or do or wear, but that's just not me.''