Whole house/multiple chunks disappeared in my realm

So recently I went back on a realm that i had spent a lot of time in building, mining and decorating. But when I went back to my house it had completely disappeared and all of the stuff around it did too. Everything else in the server in exactly the same but my area has not only missing buildings, but weirdly also remnants of the house and area remained such as a previous structure my friend was building underwater except that only the skeleton remained despite her completely decorating and designing the whole thing. I should mention that the house was also hers i just built a small house inside of it. Almost as if only my chunks were reset to previous saves. This happened right after my Minecraft updated the newest version. All my stuff in my inventory was completely the same but everything else vanished. The absolute weirdest part of it though, was that no one remembered there being a house there, or any sort of building. And every single person adamantly argued that my friend had never built a house on the realm before either. I'm so utterly confused because I know this house existed for a fact. Aside from my plentiful memories of actually building and living in my house i also have one of my streams downloaded of the house in its entirety. But when I showed everyone they thought i was just messing with them. Is there any chance that there's a bug that a few chunks could've reverted to a pervious save and than everyone somehow forgot? Am i in just a completely different universe or something?? If anyone can help I would beyond appreciate it and you. I'll include some pictures for the evidence. 

P.S. I'd also like to say that while my friends are capable of doing something like this as a joke, its also nearly impossible that they would keep it a secret as their favorite part of messing with people is ALWAYS the reaction when they find out. They're also not just complete dicks so keep that in mind too.