He never should have believed Talia.
In retrospect, it seemed obvious. Bruce knew he could have a bit of a... blind spot, where Talia al Ghul was concerned. And he does believe, every time, that he knows better. Clearly he does not.
Because she'd convinced him, hook line and sinker, that Daiana was up to something. That she'd fallen back to old ways. That she couldn't be trusted. Ironic, in a sense. It might be darkly funny, if it didn't strike so deep - he knew better. He'd thought he did. How many times had he assured Selina he truly did trust her? And then, when the chips were down... he hadn't.
There'd been arguments. Yelling. She'd tried to plead her case, but Talia had laid the dominoes well. And he'd gone and pushed them right over. He'd thought he held undeniable evidence of Catwoman's betrayal. The words he'd said when he sent Daiana away, banished her from his home and his life... couldn't simply be taken back.
And yet, when the League of Assassins sprang the trap? Daiana had come back. Clever cat, she'd seen it coming, unraveled the threads, and despite everything that had happened between them? She'd come to his aid.
Bruce wished she hadn't. Then she wouldn't be lying in pooling blood on the warehouse floor.
"Cat..." He flung the last, now-unconscious assassin to the ground - deposing them before attending to her had taken precedent by necessity - and rushed to her, heedless of his own injuries as he dropped to his knees by her side. "Daiana!"
No no no, this couldn't happen. Not like this. He'd been tricked to think he'd lost her once already - he couldn't lose her for real now. His mind spun, grasping at options - if Oracle could get the Batmobile on site - or the Batwing? - he could rush her to the Batcave infirmary. Could he get Leslie there in time? Was a hospital a better move? She'd never forgive him for revealing her civilian identity like that, but if it meant she survived...
If ever he'd prayed a cat truly did have nine lives, he was praying it right now.