Mums comments not helping

I love my Mum don't get me wrong but I try to talk about the things that I remember about the relationship and she calls him nasty names which doesn't help. This was a man that I was going to marry and I know that the way that he no 1 cheated was wrong and no 2 after we got back together and had commitment ceremony and were planning a life and talking where to get married and he couldn't wait 3 weeks of silence and ignoring letters text and calls very wrong and even more hurtful since he had promised to never hurt me again...but I feel that it still doesn't give her the right to call him derogatory names as it is her opinion of him and although he definitely did wrong...Its not helping my healing process and only rubbing salt into my wounds...I told her I love you but please listen dont label and I know he was wrong and I will get through but no name calling please.getting there day by day