I used to self harm

I used to self harm. It was like a 8 months ago. Then i started therapy and never did that again. But i never tell this to my parents. The summer is coming and my scars are as big as i cant hide them. I have to explain my parents that i used to self harm. Last time they find out, they were so angry and they worried about what other people think about our family so im afraid to tell them. Is there a way you can offer me?