If you are about to turn 35, then prepare for the most miserable decade of your life.

Increasing work hassles, money worries and loneliness mean people aged 35 to 44 are the unhappiest in society, a study by counsellors Relate said.

The age group came out worst in a series of measures, with 40 per cent saying they had been cheated on by a partner and 21 per cent complaining of loneliness a lot of the time.

Relate said it shows the mid-life crisis, traditionally the territory of those in their late 40s to 50s, is affecting younger people.

Nearly a third of 35 to 44-year-olds said they had left a job because of a bad relationship with a colleague, with a similar amount thinking their family relationships would improve if they worked less.

A quarter also wished they had more time for their family, and 23 per cent wanted more time for their friends.

The survey revealed that busy parents are using Facebook and similar social networking sites to stay in touch with children.

Relate boss Claire Tyler said her counsellors see more 35 to 44-year-olds than any other age group.

She said: “Traditionally we associate the mid-life crisis with people in their late 40s to 50s, but the report reveals that this period could be reaching people earlier than we would expect.

“It’s when life gets really hard – you’re starting a family, pressure at work can be immense and increasingly money worries can be crippling. We cannot afford to sit back and watch this happen.”