The boyfriend of a Wellington mother of two stabbed to death in her Miramar home is giving evidence in the High Court murder trial.

Tani Hoyhtya met Mei Fan in February 2011 at a restaurant in China.

"We were deeply in love and lived together for seven months," Mr Hoytya said.

When Fan travelled to New Zealand, Hoyhtya said they stayed in contact daily through social media, including Facebook and Skype, and the couple would often text and call each other.

Mei Fan's estranged husband, Michael Preston, is standing trial for Mei Fan's murder and a second charge for breaching a protection order two years ago. He denies the charges.

The court heard Hoyhtya travelled to New Zealand four times to be with Ms Fan.

He told the court he and Fan would go hunting and fishing.

Earlier, a friend of Preston and Mei Fan told the court about his sexual relationship with Ms Fan.