She should be confronting the boyfriend first, then worry about murdering the other woman.
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That's the part I don't get. Why confront the woman?
It's the cheaters butt that needs straightening out. I would invite the other woman out for a drink.
There's the possibility she doesn't know, ...and learning about her would give guidance on how to proceed.
Years ago, this guy I knew was sleeping with 3 of my girlfriends. It wasn't serious with any of them, they were all using him for his ...ahem skills
, but he pretended like each one of them was the only woman in the world. They all knew he was seeing other women, ...and I felt extremely uncomfortable because I knew all three. They'd dish holding nothing back. The hilarious part was his MO didn't change from woman to woman.
About 2 months later, he started hitting on me. I was so grossed out I said to him point blank:
"Oh Puleaze! I suppose next you're gonna ask me ________________?"
You should have seen his face! That was precisely the very next question that was about to leave his lips.
He turned bright red, and said "You obviously know a few things about me". I had to laugh out loud at that point, ...and said "Yeah! Too much to ever let you get any closer. Save it for someone who might be impressed by it, ...'cause I AM NOT THAT GIRL!" A few weeks later, I was dining with the other 3 women, and who should walk into the restaurant? ...yep you guessed it. He was entertaining a client. Talk about uncomfortable. That poor guy was squirming in his seat the entire time.
Everytime laughter erupted from our table, he sank in his seat just a little bit more.
He obviously thought we were talking about him, comparing notes, and laughing.
And you know what... he was right!