Upcoming film Cake, starring Jennifer Aniston in a Golden Globe-nominated role, comes to cinemas this Friday. The critically-acclaimed movie tells the story of chronic pain sufferer Claire Simmons, who finds herself exploring the boundaries between life and death, abandonment and heartbreak, in a last attempt to find salvation. Chronic pain affects 10 million people in the UK and can be caused by diseases such as arthritis and fibromyalgia, as well as developing after serious accidents. It is defined as…