for the loss of your guinea-pig.
You have a boar now who is 'in mourning' so keep an eye on him, lots of cuddles and see how he goes.
Your GP in the kitchen will have lots of interaction in the daytime (mine live outside in their Pighouse)
One of my boars died in July (he would've been 3 last week) and our remaining boar went very morose .He was sleeping in my DD room at night and in his Pighouse by day. Our boys need their space so keeping him indoors all the time isn't an option (their nightcage is 4'x2' and they are very judgey).
We got a little 6 week boar from Rescue after a week - and yes, it does take a bit of planning (steam cleaning the cage to remove all pig smells) . Watching them (neutral territory). And our older boy having this tiny very dependant piglet who was new to everything and practically welded to the older boars side. 
I'm 100% glad we got him. They have the odd spat , but now GP3 is mature (about 5 months now) , he's huge. Heavier and bigger than GP1. He did go through a stage of trying to mount GP1, I think that's stopped.
But there's alot of hours in the day, and night , when they are on their own, GPs are active dawn and dusk to poo eat and forage ( crepuscular).
Even if they don't sit together they have a same species companion to share the day with .Potter about in the hay. Tussel over food and popcorn.
And my DD got her baby piglet that she coveted.
And we rescued a piglet (our two original boars were adult rescue)