Sharing Our Innermost Thoughts

When I was 13 years old I was sexually harrassed by a guy who was 4-5 years older than me he touched my private part whenever he got a chance to sit with me in school bus he lived in the same building as me so wehad the same stop. So I used to ran away as fast as I can towards my house whenever I got down from the bus. After a month or two when it started happening my bus was changed it was a relief for me in bus but whenever o saw him outside my house I freaked out so I never went out and due to that me and my friends got distant and I had no friends near my place and due to that I don’t mix up with people much and I never told my parents about it because I was scared I don’t know of what but I was scared after a year his family shifted to another place and I finally stopped worrying about him touching me again but there was always something bothering me and in my school I hardly ever saw him because he was my senior. I am 21 years old now and I never told my parents about it. Sometimes I have a break down thinking about it and thinking about how many people he would have done the same I wished I took a step at that time so that someone taught him a lesson. This is the first time I am opening up about this. Should I tell my parents now? Is it okay to open up now? And is it okay for me to go to a therapist?