Clare Teal: The shocking truth about two 'strangers' on a train

By the time we got to Cheltenham, a sore throat and headache (born purely of paranoia) was developing nicely.

Reaching into my bag for headphones to drown out the spluttering, I overheard two young women across the way openly discussing their various drug addictions.

Only one girl was visible – smartly-dressed, mid-20s. The details of their exchange were graphic and shocking but I couldn't help but listen and I don't think I was alone as the rest of the passengers were also bizarrely quiet.

The plot thickened when, a few minutes later, they were joined by an extraordinarily loud woman from Dublin. As the conversation developed, carriage B learned that these girls had just been let out of prison that very morning.

I'm ashamed to say that my first thought was to gather everything I owned closer to me, but, to be honest, an hour later I just felt sorrow for these girls who were wrecking their lives, not to mention those of their families, by stealing to pay for drugs.

I felt some glimmer of hope when they mentioned how good it felt to have been "clean" for nearly a month, then terribly disappointed when, in

the same sentence, they salivated over the ordered supplies that were waiting for them at home.

The Irish woman was desperate to get back to her children, and spoke of them with such pride, saying that from now on she wasn't going to start drinking at 9am – she was going to try to wait until at least 2pm because she'd have a better chance of staying out of trouble.

The saddest part was the final exchange between the two best friends who had supported each other during their time in prison.

"I gave you my number, yeah? You will keep in touch?

"Yeah, man, course I will... but I don't know your name."

"It's Caroline."

"Hi, I'm Natalie."