Congratulations. You are now the pig parent of a teenage boar! They have a tendency to sulk, to stomp, to shout, to make pathetic attempts at what they think is "manly" behaviour, to argue and pick fights with other boars, to be fussy about food, occasionally resistant to cuddles, then want cuddles, to smell pretty awful and not be very fastidious about grooming.
The only good thing is it tends to last only a few months in boars, not years as in humans! :)
I'm on boars 7 and 8 and only once have I had to actually separate two - that was boar 6 who was nearly four when boar 7 arrived, aged only 3 weeks. Initially, the arrival of a new bub brought out boar 6's maternal side, which I never expected as he'd always been quite a spikey and bossy pig. No, he adored his young protege, until he did a Harry Enfield Kevin The Teenager Transformation into "Teen Boar."
Eventually, the arguments escalated until teen boar got a nip on the ear (probably deserved,) so I wired up two grill racks as a temporary barrier down the middle of the cage. I swapped their sides each day so they would still have each other's smell and still see and hear each other. They stayed like that for a few weeks and then I went through the full ritual of reintroducing them - thorough scrub of the cage, new toys, food dishes, etc. and a serious bath for both pigs. They were actually find after that, apart from the odd argument.
So, it might be that the separation won't have to be permanent. Give them a bit of time to "cool down," and try reintroduction?
Boars 7 and 8 still get into set to's occasionally, and sometimes there is teeth chattering that sounds pretty awful, but doesn't erupt into actual violence. Boar 8 is younger, but was "top pig" from the moment he arrived at age 9 weeks, full of confidence and assertiveness. (He's an Aries you see.) Although it's not very "fair," what usually happens is if they've had a bit of a spat, Boar 7 backs down and goes to sit in his basket rather than carrying on with the argument. Boar 8 feels satisfied that he's "won," and it all blows over.
Good luck!