If it came down to it, Castiel would turn to the Winchesters for help or would find a way to fend for himself, it would make her happier. He wasn't looking to make her feel caged in by her looking after him and playing the role of his care taker. He knew he was asking a lot of her, that much was not unnoticed to him, but he also needed someone. The most natural choice was to turn to her. Natural, although it was unnatural for him to need all of this attention and assistance, because aside from when he looked to her for guidance when she was looking after him in the hospital and when his mental state was compromised, he didn't need looking after. He didn't need someone to ensure he wasn't going to do something that caused harm to himself or otherwise put him into a potential position of peril.
"This is just as unnatural to me as it is for you." He stated after a moment, because his frustration was also thanks to how this was completely different for him as well. Even if he was used to that point of trusting her and looking to her to guide him. "I wasn't truly in this position, when you were my care taker before. I was still an angel. I still had the idea of my mission, how I wanted to atone for what I'd done to my brothers and sisters in Heaven." That was always his goal, to make up for what he'd done and to be forgiven what transpired. This, here, was completely different territory for him.
What did he want from her? He wasn't sure. Other than to allow for him to remain at her side. To not run away and leave him wondering at the end of it all.