Is it permissible to boycott a Muslim who assaulted me by hitting, knowing that reconciling with him will make him scornful and mock me, and I will not be able to stop him?

The basic principle is the prohibition of a Muslim forsaking his brother for more than three nights, unless associating with him would cause harm to the forsaken person in his religious or worldly affairs. In such a case, it is permissible to reduce communication with him to the extent that does not cause harm. The prohibited forsaking is removed by greeting him with "peace" (Salam) or similar gestures, according to the majority of scholars.