Just started the game and I'm saddled with two uncontrollable units. WHY‽

I don't know if I'm just a noob, but I find myself just ripping my hair out when it comes to Delita and Argath. Everytime I lose a fight I just think "that would have gone differently if Delita didn't charge straight onto the enemy position or Argath wasn't fucking around in one corner of the map!". Is this a normal feeling? I need to rant about these two. I'm just trying to learn the game, why do I have to micromanage my fights based on these two dimwits‽