Paranoid schizophrenic James Bryceland, 47, was found not guilty by reason of insanity at the High Court in Glasgow of murdering Jacqueline Hughes at their Anniesland home on August 19, 2007.
He was ordered him to be detained without limit of time in Carstairs.
Following a fatal accident inquiry at Glasgow Sheriff Court last year, sheriff Norman Ritchie QC has ruled "there were no reasonable precautions whereby the death of Jacqueline Hughes might have been avoided".
In a written judgment he also said that there were "no defects in the system of working" which contributed to her death.
The inquiry also heard Bryceland had been a heavy cannabis user.