Melksham man Richard Newton killed his wife Suzanne in their Bowerhill home last year while suffering from severe paranoia.
At Bristol Crown Court this morning Mr Justice Neil Ford imposed a hospital order on Newton, 51 under section 41 of the 1981 Mental Health Act, as he was suffering "paranoid schizophrenia, or a similar paranoid condition."
The court heard Newton had suffered with paranoid delusions since a horse riding accident in 2006, and had his medication discontinued in 2011, despite his wife expressing serious concerns about his condition.
The couple lived 'separate lives' at their home on Barnes Wallis Close, until Newton stabbed his wife of 20 years twice in the chest on January 12 last year in her bedroom.
He then fled to his brother's house in Somerset where he confessed to the killing, before fleeing to Exmoor, where he spent the night.
He inflicted wounds on himself to aid with his claim of self-defence, before travelling to his sister in Devon, where he was arrested.
He was initially charged with murder, but a guilty manslaughter plea on the grounds of diminished responsibility was accepted by the court in November.
The order means Newton will be confined to a secure psychiatric hospital indefinitely, and cannot be released without substantive medical evidence, and will require close psychiatric monitoring for the rest of his life.