Was it Wrong?

 My husband and I have been separated, and we have encountered some issues. I called him to clarify things. He was with his mother, so he mentioned he would call me back later. While I was speaking to him, his mother could be heard in the background saying, "Yeah, tell her I can hear her all the way over here too. She can’t wait... etc., etc." (she went on). I responded, "Why is she getting involved? Tell her to back off." She persisted, and he didn’t pay attention. Instead, he told me, "This is your fault; I told you we would talk later." I replied, "Okay, but why aren’t you addressing her?" He continued to blame me for calling, claiming that I bring all the problems into this family. Since he refused to confront her, I told him to ask her to "shut up with her nosy behavior." At this point, I was already upset because my husband wasn’t supporting me from the start; he was siding with her and allowing her to feel empowered over me, refusing to put her in her place. She had the nerve to intervene and disrespect me whenever she pleased. Was I in the wrong?