As Kirsty was losing her baby, and nearly her life, her partner was with another woman.

When 27-year-old Kirsty Rathbone, from Liverpool in the UK, learned she was pregnant with her boyfriend’s baby, she was overjoyed.

She’d only been dating Gary Edwards – who she met on an internet dating site – for a few months, but the pair had already begun searching for homes to move into together.

“Gary was over the moon and the news made us more determined to find a home together,” Kirsty, already a mum of two daughters, told The Sun.

“Finally, our perfect family would be complete.”

But when she woke up one morning covered in blood, she knew something was wrong.

She and Gary rushed to the hospital's emergency department. Doctors couldn't find her baby, and told her she would need more tests to discover what had gone wrong.

Kirsty said she was "terrified" throughout the process, and to make matters worse, her boyfriend Gary was hardly around.

When doctors told Kirsty the worst possible news - her pregnancy was ectopic and they needed to remove the foetus immediately or she could die - she was "heartbroken".

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"I rang Gary and he promised he'd be there for me before I went into surgery," Kirsty said.

"But the next day, as I was being prepped for surgery, Gary was nowhere to be seen."

When she woke from surgery, Gary greeted her with a big bunch of flowers - "all my anger faded away," Kirsty said - and after her recovery, he moved into her home.

But just a week later, Kirsty's phone rang. On the other end of the line was a woman claiming she was Gary's girlfriend.

Mum, 27, who nearly died after suffering an ectopic pregnancy tells of heartbreak after discovering her boyfriend … https://t.co/cHCyvWLavb

— The Sun Woman (@TheSunWoman) July 31, 2017

It was then that Gary's double life was revealed.

"She told me he was even with her when I was in hospital. I was stunned," she said.

"As I was losing our baby - and very nearly my life - he'd been cheating."

But there was even bigger blow to come: earlier the same year, Gary's mistress had also been pregnant with his child.

Kirsty was unable to contact Gary to confront him out the claims.

"I was devastated, I'd just lost my baby and my boyfriend," she said.

"My girls were heartbroken when Gary didn't come home. They'd grown so close to him and his betrayal hurt them too."

A few months later, the pair met up for dinner where Gary apologised for what he had done.

As for Kirsty, the mum of two said it took time to heal from her heartbreak, but now she feels "stronger than ever".