I have received a legal notice from a law office asking me to refrain from contacting their client directly of indirectly

I want to know how to go around this matter as I have received such a notice. I think I got this notice as I had emailed my ex-friend about the atrocious behavior of her husband with me. He was unfaithful to his wife and had raped me in 2007. as I was ashamed of this and did not say to anybody, he took complete advantage of it an wanted to continue the sexual behavior. he did this to other women too. His actions was caught by his wife in 2012 and after that the family stopped talking to me. We were family friends since 1998. I am going through depression because of this. The husband of my ex-friend blamed me as I did not speak up for myself. Now I want to stand up for the in justice done to me and I contacted them for answers through email as they did not answer my phone calls. Because if my emails they sent a legal notice not to contact them. I want to address this matter and I want legal help.