An expat Brit stabbed his Spanish wife to death shortly after having sex with her at their Costa del Sol villa, say prosecutors.
They believe Geoffrey Elton, 56, tried to strangle Gloria Tornay, 58, then chased her with a knife.
The retired businessman is said to have flipped after his wife of about 30 years planned to leave him.
Police found him soaked in blood after stabbing himself next to her body at their £450,000 four-bedroom home on March 9 last year.
Elton has been held on remand in prison ever since and details of the case have only just come to light as he is charged with murder.
An indictment submitted to a judge states: “Geoffrey Miles Elton was in the home he shared with his wife and their 15-year-old son in Estepona and, with the obvious intention of ending her life after having sex with her in their bedroom, suddenly and totally unexpectedly began to hit her in the face as he put his hand over her mouth to suffocate her.
“He then proceeded to strangle her and when he wasn’t able to achieve his objective, used a 5.7-inch long kitchen knife to stab her 11 times.”
Officials added: “After what happened, the accused expelled their son from the property, threw his mobile phone, that of his wife’s and the home phone outside, and shut down power.
“This was done with the aim of ensuring the success of his actions by making it impossible for the emergency services to arrive in time and stop anyone entering the property to help the victim.”
Pals say Elton had a brief fling with another woman three years earlier and had become paranoid and reclusive in the run-up to the killing.
But days before, photos on social media showed him and his wife in a loving embrace at a beach bar.
The dad of two ran a satellite installation firm before retiring aged 50 to divide his time between Spain and a Florida holiday home.
Prosecutors believe he suffered from a rare mental illness which distorts his appreciation of reality.
But a well-placed source said: “Although they accept he had a disorder which led to him suffering delusions, they don’t feel it exempts him from criminal responsibility.”
Prosecutors want him jailed for 14 years if found guilty and have demanded he pay her two children £180,000 in compensation.
A trial date has yet to be set.