No problem micokeman and welcome to the boards!
You should consider the minions attacking the companions--the companions never leave the "companion line." Rather, minions are placed in front of the companion they are assigned to.
After a companion is killed or a minion wins a skirmish and all Response events are played regarding that skirmish, the minion is no longer assigned to that companion. You can just move the minion to the middle of the table. If that minion is Fierce, then another assignment phase and skirmish phase will take place after the last skirmish from the first skirmish phase takes place.
When the Free Peoples' player ends their turn and reconciles their hand, your minions are discarded. So if the Free Peoples' player decides to move again, your minions remain out there!
Does that make sense?
-wtk
Edit: Also, feel free to check out the Archives of Minas Tirith section of the boards for rules questions!