The body of Wendy Mann, 26, was found on her kitchen floor in West Bromwich in August 2015.
Leroy Sterling, 63, of Guns Lane, denies murder and the earlier attempted murder of her lover, Trevor Tyndale, Wolverhampton Crown Court heard.
Pathologists found multiple fractures in her neck, a pattern "commonly found in people strangled," the jury heard.
Mark Haywood QC, prosecuting, told the court Ms Mann's brother became worried when he could not contact her.
He went with his wife to his sister's first floor flat on Chapel Street where they found her body.
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The prosecution alleges Mr Sterling attempted to murder Mr Tyndale on 11 July 2015 after learning of his ex-partner's relationship.
The two men went drinking at Mr Sterling's flat where the prosecution claims the defendant attacked Mr Tyndale, 52, with a blow to the back of the head.
Mr Sterling continued the attack, "forcing a knife into his neck, trying to choke him", the jury heard.
The prosecution told the court Mr Tyndale managed to escape Mr Sterling's flat and later went to hospital where he had an emergency operation for his injuries.
Mr Tyndale did not inform police about who attacked him fearing his affair would become known to his own wife, Mr Haywood claimed.
The trial continues.

Ouseph, 30, became the first Englishman in 27 years to win the men's singles title with a narrow 21-19 21-19 victory over home favourite Anders Antonsen.
The husband-and-wife Adcocks beat Danes Joachim Fischer Nielsen and Christinna Pedersen in the mixed doubles final.
Scot Kirsty Gilmour lost in the women's singles final to Carolina Martin.
The Spanish top seed triumphed 21-14 21-12.
It is the first time England have won two golds at the Euros since 1988, when Darren Hall won the men's singles and Gillian Clark claimed the mixed doubles title with Danish partner Steen Fladberg.
The success at the Euros comes after GB Badminton had all its funding cut by UK Sport before the 2020 Tokyo Olympics.
Ouseph, who had previously won two bronzes and a silver in the men's singles at the European Championships, is just the third Englishman to win the event with Steve Baddeley the previous player to triumph in 1990.
Between the wins for Baddeley and Ouseph, players from Denmark had won gold in eight out of nine European Championships.
The second-seeded Adcocks took full advantage of their first appearance in a Euros final to see off top seeds Nielsen and Pedersen, who had won the event in the past two Championships.
The Adcocks were pegged back after winning the first set but held their nerve to triumph 21-17 18-21 21-19.
A mother-of-three was strangled by her ex-partner after she began a new relationship, a court has heard.
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England claimed two gold medals as Rajiv Ouseph and Chris and Gabby Adcock triumphed in finals at the European Badminton Championships in Denmark.