Parasitism and mutualism are mutually exclusive; parasitism harms the host, mutualism helps both.

If we look at parasitism among lifeforms, it often evolves into something resembling mutualism. I think the distinction is not so clear cut. Even some forms that look like pure parasitism, can sometimes be observed to help the host -perhaps only in unusual circumstances. The parasites may defend the host against an occasional external threat. In any case, it is in the interest of the parasite, that the host survive, and possibly even prosper. So even for initially pure parasitic relationships in human societies, and not just in nature, there exists the possibility to negotiate a more cooperative relationship.