as others have said, put the person on ignore. you won't be able to see any of his/her activity.
i would like to add: the internet can be a wonderful tool. we have to keep in mind that on CC, we have people from all walks of life and backgrounds, including experiences. when we post on the forums asking a question or advice, we will get answers from all directions. that is a risk we take each time we post. also, since it's all typed, tone gets lost in the words. a person could be typing in a nice tone (to him/her) but the person on the other said reads it differently.
we can't control how a person responds to our posts, but we can control how we react to it. let's try to give each person the benefit of the doubt. let's do our best to keep the peace and be respectful with all