They’ll wander forever through an ever expanding space, meaning they probably won’t ever come across a different particle.
Eventually everything will reach equilibrium, aka the state where nothing moves anymore because everything it could react with is too far away to cause any reaction.
Which will eventually happen to all black holes because the last things remaining will be black holes, so there would be no matter to absorb.
Which begs the question, what happens to the estranged particle that escapes the black hole from hawking radiation.
They’ll wander forever through an ever expanding space, meaning they probably won’t ever come across a different particle.
Eventually everything will reach equilibrium, aka the state where nothing moves anymore because everything it could react with is too far away to cause any reaction.