Good afternoon BigK,
I inform you that it is not forbidden, never was and never will be, each player has the right and freedom to play with whom they want, I know that it is hard to understand this option of choice by these players, but we just have to accept and respect their choices.
As for playing with friends, it is normal and understandable because after all we are human and create bonds of friendship with other players, now in that which refers to "the player play with himself" that no! this is illegal and goes against the stipulations of our rules, when you have evidence of this, we appreciate that you make us through a report of abuse.
Regards
Dav7d