Disrupting enemy force combos

[Agincourt]

Okay so whenever I try to do a force combo, I am hit and then I can't complete my attack. Like with a saber sling, I get hit and the whole thing is stopped. I can get that.

 

Why then, when Maris Brood is about to throw her lightsabers at me, does an attack on her do nothing to stop it? When I get hit, my attack is disrupted, so naturally when they get hit, their attack should get disrupted. It doesn't.

 

When General Kota, Darth Vader, Kazden, and the shadow guard all set for making an attack, I should be able to hit them to stop them from using their power. How do you overcome this, or how do you make it so that they can't disrupt you when you are doing a combo? Thanks.