DE: How to control monks? They keep wandering into battle and getting killed

Monks are making me so mad.

• I'll have a group of them standing back behind my castle.

• Send my horses/whatever out to fight, then run back and stand next to monks to heal

• In the middle of battle I'll notice half my monks have walked all the way into the battlefield and are getting stabbed

They seem to have a mind of their own and even if I have monks standing a reasonable distance back, they eventually just wander everywhere.

Is there no stand-ground option for monks?

How do other people manage monks?

I'm not a "competitive" player so it's not a discussion about whether I should be using monks or not... I just play against AI and want my monks to stay put!