A cousin of mine I do not get along with

I have a cousin that I do not get along with which is like oil and water. My cousin Lester, there are times I want to slap him good at times. But I do not. We have not been getting along since growing up. He is 10 years older than me,he is 56 and I am 46. Last straw was when he sexually assaulted me when I was 17 and got away with it. He was drunk and got behind me groping my breasts. I did press charges, the charges were dropped due to he got a good lawyer to drop them. The cops and prosecutor gave up on me.He was there last night when I seen my dad whom is going down hill with Alzheimer's on his death bed now. Gave me a nasty look and I wanted to smack him.Mom was there and told me not to do it. I told him to f off and gave him the middle finger when I left. My family is concerned I will kill him one day. I call him Lester the pervert to this day.