In a 3-way system it will always appear like the other 2 factions are working together against you. As a matter of fact they are, since when one faction "A" pushes here or there, it often makes sense for your faction to push somewhere that becomes vulnerable as a result of faction "A"s push.

There is some truth to the animosity between factions, but I think it is mostly confined to a few individuals and/or guilds.

There was also a time when EP was the 800lb gorilla faction which led many to come to resent them, but that goes for any faction that has a large population imbalance and uses it to keep the opposing factions pinned down at their gates. To be fair though, depending on the server, other factions have done the same thing.

My advice is to ignore the drama and keep a "nice fight" attitude (for as long as your frustration will allow)

I've seen rumblings of particular guilds calling a truce for something or players in that guild steering one way or another (even that seems pretty rare), but the whole or even a large part of an alliance - no. Most of the time you'll see smart play going on where leaders realize that certain pushes will trigger certain behaviors. For example if you are pushing emp keeps and all three factions are fighting with strong pops, you should realize that if you cut off the ability to the other two to fight each other by taking their emp keeps, then you can't be shocked that they both push back and keep pushing for a bit. Same as if you have enemy scrolls - they will come after their scrolls, sometimes they will come after any scrolls easy to grab, even the other enemy scrolls. Sometimes one of the three will feel a bit a bit weaker than one of the others making a big push and will try and ride their push on the other side because they don't want to fight them at the moment either. There are a lot of things that can trigger certain scenerios, more than my examples and 99% of the time it's something like that and not anyone actually working together.

This stuff happens all the time.

For instance, when you play in cyro long enough you begin to fight the same people over and over. Then you msg them. Then y'all become friends. Then you escalate to tbags on each other. Mostly in good fun. At some point, you frenemy on another faction needs to be dethroned, so y'all team up and run the inner keeps. Or y'all decide to troll the scroll together. All of which makes pvp way more fun than otherwise.