A woman on Reddit was furious with her husband after his best friend's 18-year-old sister, whom he has long been close with, sat on his lap and flirted with him shamelessly at a dinner party.

"My husband Jake and I have been married for three years and from the beginning he was very close with his best friend's sister Cindy. My husband would often talk about her and tell how he had seen her grow up throughout the years. Cindy is always very bubbly and seems very fond of Jake as well. I remember when we were dating she would ask to come along on our dates a lot. I never really said anything as I liked spending time with her as well. She was like a little sister to me," the woman began.

Cindy was even a bridesmaid in the couple's wedding, where she told Jake he "better not forger her" after the wedding. However, after the couple moved states, they lost contact until recently, when Jake's best friend came to visit them and brought Cindy with him.

"The moment she saw us the first thing she said was how hot my husband has gotten and she was glad he didn't look like those boring married men. Then throughout their stay Cindy would just ignore my presence and be way too close with Jake. I told Jake that it was looking a bit inappropriate and to ask Cindy to tone it down, but he said that Cindy is just a bit childish and is that way with everybody," the woman continued.

On Cindy's last day visiting, the couple hosted a dinner party, during which Cindy told the woman she needed to "steal" her husband for a while to play games.

"Throughout the dinner she was getting way too close with Jake and would just drag him away whenever I would be around while giggling at me," the woman recalled.

Later, when it came time for dinner, Cindy exclaimed there was "no seat" for her and sat on the woman's husband's lap.

"Everybody was surprised and Jake said laughing 'Cindy, stop acting like a kid, you are not a kid anymore.' Cindy started laughing saying it was a joke and got up and sat on another seat while giggling at me," the woman shared.

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The woman was furious, and even more upset that her husband was OK with Cindy sitting on his lap. She didn't want to cause a scene, though, so she quietly excused herself, got in her car and left the party.

An hour later, her husband called and she told him she would return after Cindy had left, explaining: "I was so angry at that time that if I had stayed there any longer I would have probably started fighting or crying." But when she returned home, her husband told her she "took thing too far."

"I started crying and told him how everything made me feel. He said it was horrible to think such things about Cindy and that she was like his sister. I told him that I was not doubting his intentions but I was hurt by how disrespectful Cindy's behavior was and he was enabling her by not saying anything. He started saying that I sounded ridiculous and couldn't even take a joke (referring to the sitting on lap incident). I said regardless, I don't want her in my house again," the woman detailed.

Later, Cindy texted her with a weak apology for making the woman feel "so insecure in myself," telling her she "should not have left as it was pretty childish and kind of spoiled the mood."

She didn't respond back to Cindy, and told her husband to stop contact with her.

"This really rubbed my husband the wrong way and he said since I have such disgusting thoughts in my mind, and is giving him an ultimatum anyway, then he might as well leave because he cannot live with such an insecure person who has such disgusting thoughts about him. He packed a bag and left for his mother's place. I have tried apologizing numerous times, telling how sorry I am for everything, but he is ignoring my texts and calls," the hurt woman concluded.

Users in the comments section shared their resounding support for the woman and slammed both her husband and Cindy for gaslighting her.

"Your only mistake was apologizing to your husband, as if his accusations were fair," one person wrote.

"She had nothing to apologize for, now her apology justifies their actions as making it seem like they did nothing wrong ... I would go as far as taking back the apology," another chimed in.

"She has no reason to apologize. And the fact that he is ignoring her apologies, it's giving 10-year-old tantrum vibes," someone else commented.

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