Sarah Rudkin found out her boyfriend had slept with her sister (Image: Peter Powell)

When barmaid Sarah Rudkin’s boyfriend returned from her sister’s she smelled a rat and her suspicions were spot on.

Boyfriend Liston Dove had gone round to mum-of-three Lisa Bushell’s to do the washing as their machine was broken.

But he came home grubby having slept with Lisa.

The double betrayal devastated Sarah, 26, who said: “It broke me. I wouldn’t expect that from a friend, let alone my sister.

“The two people I trusted most in the world had betrayed me in the worst way possible.

“I was furious with Liston. I’m not an aggressive person but I felt like going to his work and beating the c**p out of him.”

“I couldn’t believe Lisa would do that to me.

"When she split up with her husband I’d done everything I could for her, looking after her three children and making sure she was OK.

“She’d repaid me – by sleeping with my boyfriend.”

Such an appalling deception would often be the death knell for a relationship. But, amazingly, Sarah has buried the hatchet with supermarket worker Liston, 29, and Lisa, 31.

Now Sarah and Liston have ten-month-old son Zack together. She said: “I’ve forgiven them but I don’t think I’ll ever forget.”

 Sarah Rudkin with boyfriend Liston Dove, who she has forgiven for sleeping with her sister (Image: Sarah Rudkin)

Liston was Sarah’s first crush when she met him at her mum Shirley’s wedding. She was 14 and he was 17. He had a girlfriend and they lost touch until 2014 when they bumped into other in a bar.

Sarah said: “It was very romantic. We recognised each other straight off and had a great night together before I dropped him off in the taxi on the way home.

“He called me a few days later and asked if I wanted to go for a walk on the beach together. More dates followed and we fell in love.

“Liston was always telling me I was the woman he was going to marry, but I was quite cautious as I had a two-year-old daughter from my previous relationship.”

A few months later they moved in together. They were desperate for a child to cement their love but, after a year of trying, Sarah was still unable to conceive.

She said: “We were seeing a specialist but there didn’t seem to be any reason why I couldn’t get pregnant. We weren’t arguing about it but it did put us under a lot of pressure.”

Meanwhile Lisa’s marriage had broken down and she was struggling alone with three young kids.

 Sister Lisa apologised but Sarah doesn’t think it can be the same between them again (Image: Peter Powell)

The sisters were very close and always helping each other.

So when Sarah’s washing machine broke down in February 2016, she asked Liston to take a load to Lisa’s house to get it laundered.

But Sarah smelled a rat the moment he returned.

She said: “I just had this funny feeling something had gone on. I had a weird suspicion but I can’t explain why.

"I sensed there was something different when we were all together but couldn’t quite put my finger on it.”

Still plagued with doubts two months later, Sarah turned to her best pal Emma, Liston’s sister.

Initially Emma was sure nothing had happened between Liston and Lisa. But then Emma changed her mind. A few days later, Emma called Lisa on her mobile as Sarah listened on a speaker phone.

And her heart broke in two as her sister confessed all.

Sarah said: “It was like a bad dream. Lisa was upset saying it was a mistake and she didn’t want me to know as she didn’t want to hurt me.

"I couldn’t listen to any more and ran out the room.”

Sarah texted Liston: “I know everything. Don’t ever contact me again.”

 Liston said: 'It was a stupid mistake and I had to grovel to get her back' (Image: Peter Powell)

That night, Emma took her to the pub where she got “way too drunk” and just sat in the corner upset.

Numb with shock, Sarah felt unable to confront either Lisa or Liston who, by now, was continually texting and calling, begging for forgiveness.

Sarah said: “I still loved and missed him, but I also hated him.”

She kept Liston at arm’s length for four months but her daughter Amelia, from a previous relationship, kept asking to see him.

In the end Sarah caved in. She said: “When he first started coming round I couldn’t even look at him.

“I’d just disappear to another room while he played games with Amelia. I was so angry. I was really down and ended up on antidepressants.

“Liston kept asking if he could take me out to apologise properly but I was still furious. About five weeks later I gave in and went for a meal with him and we spoke about what happened.

"He said he was sorry and that he would do anything to have me back.

“I realised how much I missed him. He had been my best friend, my rock, but too much water had gone under the bridge.”

Liston finally won over Sarah when he bought her tickets to the Download festival in Doncaster, South Yorks.

She said: “He was really apologetic and said he didn’t know why it had happened and that he wasn’t even attracted to Lisa.

“He said his biggest regret in life was losing me and, being miles away from home at the festival, changed something in me. I could see that I had to take him back.”

But Sarah, of Norris Green, Liverpool, still hadn’t confronted her sister Lisa.

“I just couldn’t face it. I told my mum to tell Lisa to steer clear of me. Our kids were at the same school but thankfully used different entrances so I could avoid her.”

 (L-R) Liston, Sarah and Lisa hanging out with friends, in 2016, a month before the betrayal took place (Photo: Mirror)

Sarah had nothing to do with Lisa until September 2017 when their mum Shirley engineered a meeting on the school playground.

Lisa has apologised for her “massive mistake” but Sarah doesn’t think it would ever be the same again between them.

Liston said: “I’m as mortified as anybody could be and I’m so happy that Sarah has forgiven me.

“It was a stupid mistake and I had to grovel to get her back.”

Lisa said: “It means so much that Sarah has forgiven me. My marriage had ended about a year before and I’d been through years of depression and was in a bad way.

“It was a sorry mistake. I can’t recall ever fancying Liston in the past. I think I was most likely for a bit of comfort.

"That’s what friends said to me afterwards.

“I felt awful when Sarah found out. There was absolutely nothing I could do to make it right.”

She added: “We were very close as sisters and I’m now working to build bridges.”

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Relationships;Cheating;Forgiveness