A 19-year-old woman on Reddit is refusing to attend her cousin's wedding after her cousin slept with her ex.

"I’ve got a cousin, let’s call her 'C,' who I used to be really close with, like basically sisters. Last year, I was in a pretty serious relationship with my now-ex boyfriend, 'B.' We’d been together almost two years, and honestly, I thought we were really solid. We were talking about moving in together, plans for the future, all that stuff," the woman began.

However, she eventually found out he was cheating on her with her own cousin.

"When I found out, I immediately cut ties with both of them. I couldn’t look at C the same way after that, and she never even really tried to apologize. I just stopped talking to her altogether. I didn’t explain much to my family at the time, just that we broke up and I wanted some distance from C," she shared.

Now, her cousin is getting married and her family, including her own mother, has insisted she let go of her "grudge" and attend the ceremony.

"I told my mom I wouldn’t go, and now she’s telling me I’m selfish and that I’m going to cause a huge scene by not showing up. My aunt (C’s mom) called me too, begging me to come because it would 'keep the peace.' Apparently, some family members don’t know the full story and think I’m just being petty or something, which makes me feel even worse," the woman concluded.

READ MORE: Woman Refuses to Ruin Christmas by Attending Sister's Wedding

Users in the comments section largely sided with the scorned young woman, with many blasting her mom for not taking her side.

"As a mom I am really disgusted with yours. She should 100 percent have your back here, and frankly, I don’t think she should go to and support the wedding of people who betrayed her daughter," one user commented.

"She wants you there so it appears to the family that their infidelity is forgiven. Don’t go, only doing so makes them look better and will make you feel worse. Treat yourself to a massage or something to the value you would have otherwise spent on their wedding/gift, etc. Your mom wants it to be comfortable for her but it’s not about her and they should feel ashamed," another wrote.

"Seriously, it's like you need a new family. All of them are narcissists from your cousin to your mom. I don't know what friend situation you have, but may be time to look at good ones as family. Or if possible, move and start fresh," someone else suggested.

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