Is this Sa?

Can someone please help me out? Was this sexual assault? I don’t recommend reading if you are sensitive as this story is graphic and detailed.

When I was little (about 1-4) my grandpa would touch me inappropriately, down my pants. Since I was young I didn’t know that it was bad and whenever I was near him I would open wide my pants and he would look down then say he can’t touch in case someone would see him (one of my family members). Since i was little i started humping chairs all the time, my family started seeing me do this. Unfortunately that wasn’t the end. He did this to me until I was about 8-9. One time he lifted up my shirt, sucked on my nipple and said “does that feel nice?” I said no and felt uncomfortable and disgusted. Ever since then he never did anything to me again, but I still feel disgusted and ashamed every single day and I feel like it’s my fault that this happened, my biggest regret is not saying anything earlier but it’s too late now. Sometimes I still see him peeking through the gap of the door while I’m in the toilet or while I’m getting changed. Till this day my family still think that I’m a freak because they caught me doing weird shit. I feel so disgusted and ashamed in myself and refuse to tell anyone what actually happened.