Settle in folks, this is a bumpy ride.

A post on Reddit from a woman who found out she is accidentally engaged to her brother is blowing the fuck up.

Reddit user Oopscest – a throwaway account – posted yesterday that she found out her partner of two years, whom she happens to be marrying in six weeks, was actually her half-brother, and that he'd known about the accidental incest for an entire year.

They met through a tabletop role play group and had an instant connection, she writes.

"There was chemistry between both us and our characters and, as the campaign came to a close, he asked me out.

"It was a big deal for both of us. We're both nerds -- as you can tell -- and our social circles are pretty small. Both of us have trouble getting out there and socialising. We're more the type to keep our heads down. It was only my second serious relationship and his first. After a year of dating, we got engaged. We finally moved in with one another a month ago and our wedding is in six weeks. Beyond the normal little domestic naggings, things have been perfect. He's my soulmate. I don't know what I'd do without him."

So far, so good. Oopscest describes her family as "dysfunctional", but not too bad; her dad was never involved in her life, and her mum and grandparents raised her. However, she describes her fiancé's family as "pretty much perfect", the type of fam who get together every Sunday for dinner.

"I always thought they were perfect, so it came as a shock to me that - while working on wedding invitations - my future MIL mentioned that my fiancé's dad is actually his stepdad. I asked to see a picture of his real dad and I nearly passed out when my MIL showed my a pic of my dad.

"I don't know how I kept from screaming and stayed conscious. I excused myself from the room and promptly threw up. I'm pretty sure she thinks I'm pregnant now; which is just a whole other can of worms unleashed."

But here's the kicker: it turns out her fiancé – "let's call him Jaimie" – had known for an entire year.

"I got home and confronted my fiancé about it. I was crying. I was screaming. He just sat there, fidgeting. Eventually, he admitted that he's known for a year but didn't want to lose me. Since we always planned to be childfree, he didn't see the problem with just keeping it from me.

"I'm betrayed. I'm disgusted. I'm hurt. I'm ashamed. I'm heartbroken. I don't know what to do. I've invested so much money into this wedding and much of it is non-refundable. On top of that, I don't know how I'm going to explain this to my family and friends. Worse yet, I love him. I know we can't be together; but until yesterday, I thought we'd grow old together.

"What do I do? What the fuck do I do?"

So basically, they share a half-dad and "accidentally pulled a Lannister". And you thought your (last) relationship had problems.

Considering Reddit's unusually high appreciation for incest stories, the commenters have actually been pretty supportive. Most want to focus on the two separate issues here: the incest, and the lying, though as Oopscest herself says, she's definitely more concerned about the incest.

Genetic Sexual Attraction is an extremely real and confronting thing, where blood relatives meet as adults for the first time and experience sexual attraction. For obvious reasons, little is known about GSA, but is thought to occur at even a minor level in up to 50% of all post adoption reunions.

As UK columnist Charlotte Gill wrote in The Telegraph earlier this year, most people who experience GSA feel deep shame about their feelings, yet powerless to change them. It's an utterly traumatising situation, and one that is not very well understood because, as Gill says, "who wants a PHD in incest?"

OP hasn't posted an update yet, but tbh we're just hoping they figure out what to do next. A DNA test, ideally.

Photo: Game of Thrones.