She said: ‘I was always wary of something happening, and it just shows that I had every right to be, because look at me now.’

Ms Allen was diagnosed with a bilateral pulmonary thromboembolism after collapsing while on a family holiday with her boyfriend Joe, 24, last month.

After beating scores of applicants to secure a job as a police officer, it has been recommended that she is not suitable for the role because she is so unwell.

Ms Allen will have to wait to find out if she can reapply in the future if her health improves.

After winning a silver medal and representing England in British Show Jumping events against Ireland, Scotland and Wales in 2010, she may never ride a horse again due to her health.

Ms Allen, who had been working in events, said: ‘It’s devastating. I have been interested in the police since I was 18.

‘I have absolutely no idea what I’m going to do now. Work isn’t even on the horizon.

‘I’m literally in bed every day. It’s depressing, I’ve had a massive set-back.’