If you purposely stay away from someone, you shun that person. A sensitive baker may ask why you are shunning her cookies.
Although the verb shun means to deliberately avoid anything, it has a specific meaning in certain groups and communities. In this case, it means to ostracize or expel from that group or community. The Amish, for example, may shun members of their order who repeatedly ignore the beliefs and rules of Amish society. The word may also be used in more casual group settings. After many attempts at being polite, you and your friends began to shun the obnoxious woman who never let you get a word in edgewise.