It’s a myth that all Scandinavians are happy, healthy, outdoors people. It’s often more a matter of class whether you can afford to take time to take care of yourself.

It’s almost as if the Swedes have two different personalities: one for winter and one for summer. I am both a happy and a melancholic person. It’s complex as I get so much from life. I come from a big family, I have two children, I have success… and yet I have really melancholic periods. I try to take care of my health. I’m in therapy and I exercise and meditate.

Some of the roles I play are very demanding. My body and brain can’t separate what is real fear from what is played fear. With my rational mind I tell myself, ‘This is not really dangerous,’ but my body still responds by being afraid. Spending time with my family and friends helps and I go for Thai massages, but it takes a while to calm down, to put my feet on the ground again and to be me.

For my role as Saga in The Bridge I researched autism. The biggest thing I learned is how lonely people with disabilities get. When you go out in the streets behaving like that, you can sense that people’s interest just dies.

My husband and I have been married for 15 years. He is a priest in the Church of Sweden. I have a faith, but it’s not so formal. We made our peace with that. There is a saying that when you are married you should think about yourself as two trees and not stand too close as trees can’t grow if they are in the shadow of each other.

When I’m meditating I have a picture in my head of when I’m happy and calm: when I’m in my hammock in the garden of our summerhouse. I hear the children on the trampoline and maybe my husband is sitting and reading. I hear the birds, I see butterflies, I hear the ocean, and that’s heaven.

Sofia Helin stars in The Bridge on BBC2 on Fridays at 9pm, all previous series are available on iPlayer now. Sofia is also supporting WaterAid’s Water Effect campaign (wateraid.org)