A heartbroken wife who is in the middle of a split from her spouse has penned an open letter to her husband's extramarital partner, revealing her 10-year-old daughter's sad question; "Why did the woman take daddy away?"

According to the letter, her cheating husband left her for a colleague who knew he is a married man, reports Yahoo Entertainment

The anonymous woman posted the letter to online chat forum Mumsnet, asking the "other woman" what she has gained from dating her husband. 

READ MORE: Forgiveness after infidelity: why women who stay deserve less criticism

“I just need to understand the reasoning behind having an affair with a taken/married man?" 

She says she can understand that men normally cheat to boost their egos, but she cannot seem to figure out what her husband's lover benefited from the affair. 

The woman went on to reveal that she knows that her husband was not treating his girlfriend to romantic dates, seeing her on weekends or even inviting her to their house. This is why she asks how any woman would be happy with that.

She says she cannot fathom why her husband's lover did not just find a single man who would offer her something more than a flimsy affair. 

“I’d rather spend my time looking for someone else. A meaningful relationship rather than be used as an ego boost.

“Knowing he’s cosying up to his partner in the evenings, while you’re just his ‘sexting buddy’ - where’s the fun in that?” she wrote. 

READ MORE: Modern infidelity: When cheating is a question of when not if

Her letter goes on to note that she and her husband were very happy and often went on dates and holidays.

"He was with me almost always," she explains. 

According to Daily Mail, some Mumsnet users understood the devastating blow, while others urged the distressed wife to hold her husband more accountable instead of placing the blame on the "other woman".

“Another woman did not take daddy away. Life isn’t like that. Daddy left. He left. No one took him,” said one woman.

Another added, “Where’s your letter to your partner? The other woman is not blameless. She did not take him away. He willingly cheated and left. Your anger is misdirected."

READ MORE: "I arranged a meeting with his side chick to get closure"

Cape Town-based relationship expert Shelley Lewin says we assign blame as a way of managing the shame and grief so that we can feel better about ourselves and avoid taking any responsibility. 

"The other woman is the easiest target. A third party is often blamed for being the predator or seducer," she notes.

"It makes us feel better to deny or even ignore the role of one’s partner in infidelity. We don’t want to question their commitment levels," she further reveals. 

Shelley says the best way to avoid blaming someone else is to understand that, "another woman is just a sign of disconnection.

"Instead of assigning blame, use this as an opportunity to evaluate where in your relationship you are disconnected, and how to fix it," she advises. 

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