Wow, I can't believe you had to go through that. I grew up a Sunni but I had Shi'ite neighbors so I saw some of the matam ceremonies. I will admit I liked some of the chanting and found it quite beautiful, but I wish they didn't go insane and try to actually draw blood with the hitting. Why is Islam so obsessed with death and blood? The whole Ashura ceremony could have been a dignified ritual with appropriate music and dance as a form of respectful commemoration. That's what a gazillion other cultures and religions do. Instead they have to encourage violence and self-mutilation! Makes no sense to me.
I miss the communal singing, I miss the harmonies that my mother and aunts and cousins and I would recite at these events, that was the best part for me. I loved to sing.
And yes there are many better ways to commemorate one's ancestors. I was once talking to my very religious mom and I asked her why don't Shia's just donate blood instead of wasting it by flagellating themselves like some ancient cult of death. She said to me something like "oh yeah they do that too, but the matam is an emotional thing and a tradition". I was like, what??? Even if you believe in the story of Karbala (the story Shia's believe in literally and which is the reason they spend 2.25 months at the beginning of each Muslim year engaged in communal self-mutilation), even if you believe in that story, why wouldn't you want to commemorate it by doing positive things? Why wouldn't you want to HONOR the memory of your ancestors by doing good deeds that raise their impressions on the world? No, instead we all sat around beating the shit out of ourselves. LOL. So bloody effective.