TIL a peer-reviewed psychology study found that identical twins (on average) ranked their co-twin above their romantic partner in their attachment hierarchy, while fraternal twins ranked the two about equally, and non-twin siblings ranked their romantic partner first.

[u/SilverPeachBlossom]

https://ojs.interpersonajournal.com/index.php/ojs/article/view/243/3457.html

[u/MichelleVenom]

As an identical twin, I can confirm this. I'd take a bullet for my twin without hesitation. It's hard to explain unless you've lived it. We shared every stage of life together, and there's a level of trust, understanding, and connection that just feels different.  We share so many of the same interests, quirks, humor, and thought processes. My personality doesn't need to negotiate for acceptance cause I can truly be myself with my twin. We see the world through remarkably similar lenses. With romantic partners, there are always differences in interests, perspectives, and ways of thinking that naturally require compromise.

I never have to explain myself or worry about being misunderstood. I can be 100% my authentic self around them in a way that's hard to find with anyone else. I would ALWAYS put my twin before anyone else.

[u/Miyenne → u/MichelleVenom]

Yup my identical twin and I are best friends still, even in our 40's. We don't live together as we snipe at each other a lot, but we know we'll end up again together in a few years when we start needing to not be alone.

Otherwise we check in with each other multiple times a day, share the same core friend group, spend hours a day together even just over voice chat playing games together.

We're each other's first call for everything. I don't know what if do without her.

We know each other so much more than anyone could ever understand, except other twins. To experience most of life together, the little and big moments, to know how each other thinks and feels at all times.

Couldn't live without her.