As Mr Speight slept, Natasha, 31, collapsed in the bath with the hot tap running. The cause of death was “cocaine toxicity and immersion in hot water”, with a verdict of misadventure.

Last week’s inquest heard that Natasha was such a heavy cocaine user, the drug had eaten away the septum of her nose.

Mr Speight, who was briefly arrested on suspicion of murder and supplying Class A drugs, has stayed with Natasha’s mother in Palmers Green, north London, since the tragedy.

Mrs Collins said yesterday: “Because of his fragile state of mind both Mark’s family and Natasha’s family, as well as all his friends, are deeply worried.”

Days before Mr Speight went missing, Mrs Collins revealed how she often heard him crying himself to sleep. “Mark has lost his future. His life has ended and it will take a long time to rebuild it.”

The presenter, a talented artist who fronted the BBC children’s show SMart, phoned his mother Jacqui in Wolverhampton at noon on Monday, sounding “relaxed and upbeat”. A family friend said: “They talked for a long time and he said nothing that sounded alarm bells.”

Yesterday, his stepmother Francoise Coade, 71, said: “Mark was devastated, naturally, by what happened. But he has no reason to feel guilty – he’s not responsible.”