I'm guessing she didn't actually stab him badly/deeply but he knocked himself out as he fell. I'm hoping he might come round and in true horror-movie style creep up to Helen and start throttling her just as the police burst through the door.
I don't think he's dead. But whatever happens, there's no getting away from it - after all that build-up, this episode was rushed and illogical, for so many reasons. Quite strange actually after the generally gradual pace of this storyline.
I thought the Helen actress did an amazing job , she was really good. And the dramatic tension was high, my heart was thumping. But I couldn't quite get past so many parts of the plot that didn't really make sense. Frustrating.
I wish they'd done it differently. Properly. WA and Kirsty helping Helen and Henry escape; Rob eventually being prosecuted.