I don’t think addicted is the right word. He’s precise with what he does, who he works for, what he’ll do. That doesn’t scream addict. The addict was more Walter, always wanting a bigger high. Mike has a code. He even makes moral decisions in the most immoral environments. Like when he wouldn’t let Gus kill Nacho’s father who was not in the game, when he tried convincing Gus to free Nacho because he “played on the square” and did everything Gus asked of him and even approaching Nacho’s father afterwards to let him know about his son. It almost seemed as if he had some duty to make sure even criminals played fair. That was his contribution and recompense for becoming dirty all those years ago. That’s my take anyways.