Did Pearson's departure give Mail the blues?

What did Daily Mail editor-in-chief Paul Dacre think when star columnist Allison Pearson's final column for the paper was about how unhappy she was with her life: " Depression's the curse of my generation and I'm struggling in its grasp "? Just days later Pearson signed for the Daily Telegraph . So was it the Mail making her unhappy? Janet Street-Porter gave us the answer across a double-page spread of Saturday's Mail: " Depression? It's just the new trendy illness".