What happens when two objects gets separated by the cosmic horizon? More importantly, what happens to the energy/information?
In most respects this should be the same as a black hole horizon?
Only even more weird, because here two masses gets "disconnected" from each other.
What happens to the potential energy stored between these two objects?
How does this energy increase if they are still considered connected even beyond this horizon?
Have it been asked if this energy could explain the accelerating expansion of the universe?
If the information is impossible to retrieve, does this not break a whole phletora of physical laws?
I aplogize if this have been asked before, I did try to search, but to be honest I could not even figure out how to formulate the question without writing several sentences.
 A: I assume by "cosmic horizon" you mean the "particle horizon" which is an alternative name for the "cosmological horizon".  You may want to take a look at
https://en.wikipedia.org/wiki/Cosmological_horizon .
I also assume that your concept of the universe is consistent with a model based on the best current calculated values which define the properties of our universe as they are understood today. If my assumptions are OK, I can provide an answer to your question which is consistent with these assumptions.
The first point is that the boundary (the particle horizon) is a spherical surface at a distance defined by a radius that increases in size as time passes. At any particular time the boundary is moving away from the center of the sphere (at which an observer is assumed to observe) at the speed of light. Therefore, the bottom line is that any two objects that are inside the observable universe boundary at one time will remain inside the boundary at any later time. Therefore two objects cannot become separated  by the boundary.
