No, he figured that you don't give a damn about him outliving her. It's him having to watch her die that he can't live with. Though this isn't living now, is it? As there is a lack of reaction of her screaming at him and only staring at her curled balled up on the floor.

What should he do? He can't Doctor. Not properly. Not like this. She may as well have the truth.

"I know you don't give a damn if I outlive you... But I can't watch you die."