So, I'm several hours in the game, doing the quest where I go through the fire fields to investigate that church.

Suddenly I notice my mage character is no longer able to interact with other characters by talking to them.

Trying some different things I decide not to pay the trouble any mind, but then I come to combat, when it starts and I'm controlling the mage she can just stroll around the enemies who are stuck in the combat poses and act like she is not in combat. She can cast spells and harm then but everything else is frozen like it's turn 1 of the fight.

If I switch to controlling any of the other game characters it suddenly shows me "START THE FIGHT" screen, but again. The turn-bar above is missing my mage. It's like she does not exist.

This is wierd, and my only option is to rollback the save by four hours which would not be ideal. Also I can't be sure it won't happen aganin, so what the heck is going on?