45-year-old, Lakhvir Singh killed 39-year-old Lakhvinder 'Lucky' Cheema, because she could not bear the thought of his marriage to another woman.
He was due to marry Gurjeet Choongh, on Valentine's Day 2009.
On Jan 27, Cheema and Choongh both became violently ill after eating leftover curry which had been in the fridge of their home west London.
Within hours, Cheema was dead and Choongh was fighting for her life after being poisoned with Indian aconite.
Southall-based Lakhvir Singh was found guilty at the Old Bailey court of murdering Cheema and causing grievous bodily harm to Choongh.
According to Edward Brown, prosecuting lawyer, "Perhaps jealousy, anger and revenge all playing their part, Lakhvir Singh decided to poison them using an extremely toxic and deadly poison, possibly brought especially from India."