At the beginning of last year, Henry Hendron would have been forgiven for thinking he had it all – a successful career as a barrister, representing high-profile figures and politicians, a flat in the heart of London, and a happy, loving relationship.

But just a few weeks later, it lay in ruins. His 18-year-old boyfriend, Miguel Jimenez, was dead from an overdose. Hendron was arrested and later charged with supplying drugs – his career and his freedom both in jeopardy.

In an interview with BBC Radio 4’s Today programme, Hendron has told how his partner’s death weighs heavily on his shoulders.

Last week, at the Old Bailey, Hendron pleaded guilty to two charges of possession with intent to supply Class B and Class C drugs. He will be sentenced in early May, with the judge telling him that “all sentencing options remained open”. BBC producer Alexander Parkin had earlier admitted two counts of supplying controlled drugs.

Whether or not Hendron is jailed, it almost certainly means the end of a successful career as a barrister.

He says he is not pleading for sympathy or expecting special treatment from the courts. He holds himself entirely responsible for his situation – and the death of his boyfriend.

“Every day that goes past I feel responsible. I was older, I should have known better, I was 34 then, he was only 18. It should have been me saying ‘we’re not going to do this’ … I didn’t make that call when I should have done, and for that reason, and that reason alone, I put his tragic death on my shoulders.”

He believes party drugs are wrecking the lives of many young gay men.

“It was a normal Monday afternoon. We had taken our dog to the vet. We had dinner, we had some wine, and my partner had quite a bit of wine, and then at midnight he just said ‘shall we have some drugs?’

“I was working the next day, so I didn’t have any on that occasion, but he did. He had some G [GHB]. It was quite a nice experience and we went to sleep. I woke up and he was dead, next to me.