Well, you could always put up a mundane discipline or conviction block, when facing such an opponent. You can narrate that by forcing yourself to think happy thoughts or murmuring a prayer when facing it. That's basically doing a defense roll before the attack happens.
That being said, putting up a magical block like that should be no different, and I would not allow a block against mental and physical attacks from the same spell. The reason would be in the narrative justification, which I see in turning a spell inward or outward.
For example you could call on fire to help protect your mind from the monsters, calling upon its connection to warmth, the hearth-fire, the sun and summer in general, and so forth. You would use those elements of fire magic, instead of actual fire, that could build up a barrier between you and the monster.
Other magical elements would, of course, use different justifications to put up such a block.
The all for one or one for all rule is usually used for offensive blocks, I think. Like you can either block all actions on one target or one action (for example movement) on multiple targets.