My closest friends have completely abandoned me, what do I do?

I'm currently at university, and about 6 months or so ago I made an initial agreement to live with my 4 closest friends. About a month ago, two of these friends told me that they would rather revert to a prior agreement made between the 4 of them to live with each other. I was never aware of said agreement and was pretty annoyed that it had taken that long for them to tell me about this initial agreement that I wasn't privy to or even a part of.

Despite this frustration, I knew I had another one of my close friends who I could live with. This friends was also good friends with the other 4, and agreed to live with me. Last week he told me we need to talk about housing for next year and I just sensed that not everything was alright. He told me that he had an agreement with 1 of the 4 friends to live with them, and that he had agreed to live with this friend as well as the rest of them in a 5.

I'm yet to hear everybody's side of the story, but I have been misled by everyone involved with people choosing not to tell me vital pieces of information. I've been lied to by the people I considered myself closest too and I can't see how my relationship with any of them will be the same again.

On top of all this, the 5 of them represent the 5 people I would have most ideally liked to have lived with. Now, because I've been told so excruciatingly late in the day, any other options that would have been open to me are now not available. Other friends have made housing arrangements amongst themselves and I've been left to fend for myself.

The situation has left me with a lot of questions. Have I completely misinterpreted my friendship with these 5 people? (Considering that I have spent most of my year with them) Am I right to feeling as aggrieved about the situation as I am? Can I remain friends with them? Should I?

The worst part about all this, is that it's the 2nd time in 3 years that a group of friends that I considered the closest to me have treated me so badly. 3 years ago a group of friends (comprising of a handful of my closest friends amongst others) hopped on my best friend of 14 years' private jet to the Caribbean for his 18th birthday. I was never told about this and had to find out on Facebook after a couple of friends got sloppy. It was my last year of school so I chose not to bring it up and grin and bear it, as a I was going to university in a couple of years.

I guess I'm as distraught as I am because I felt really close to these people. I was so happy to make such good friends, and now they've all turned around and betrayed me in a fashion I that never could have fathomed possible. I'm genuinely at a loss in terms of how to proceed.