Andy doesn't believe Ronnie's sincerity.
"I" here, Ronnie pointed to himself, "want you" he pointed to Andy, who only made a low noise somewhere in his throat, "get clean" here he mimed showering. The younger of the two was wondering whether he should laugh at that, or not. He opten not to. Instead he asked, "You want me to help you get clean?" after a very tense silence. He had the feeling that at any moment, Ronnie would jump up and yell "Fooled ya! Ya fell for it!"
Instead he got the answer, "Yup."
The younger breathed a sigh of relief. Though he would never say it, even to himself, he'd been waiting for years to hear that. But a sense of doubt still remained, so he asked, "Are you sure?"
Ronnie looked him dead in the eye and replied, "You said you'd help me in any way you can, no matter what." A smirk twitched at the corner of Andy's mouth. "Yep, I sure did."
Despite the sly smile on Andy's mouth, his internal feelings were in conflict. Yes, he had promised Ronnie that he'd always help him no matter what. On the other hand, he knew that Ronnie's issue with drugs was massive, and to end it would be hard, if not impossible, with just the two of them working on it.
"So will you?" ROnnie asked, somewhat sheepishly, dragging the younger out of his thoughts. "Of course." Andy said, all the while mentally bracing himself for the following weeks of hell.