If you scroll to the right of their newsfeed, there will be, I think an x pop up, or there is an x there, or something, and then you click it and it will pop up with questions, asking you if you want to block their feed. I will double check and if it's something more to it, I will post again, but that explanation should do it. I think it helps to block people that are too much. That way you can still have contact via FB email, if you want, and they can contact you, but you don't have to see every detail all the time. They also will not know you block them.