Interesting subject this.
Something 'overshadowing' your past, or at least, something big that happened in your past that still effects you today, is definitely worth talking about when depression is a factor in your life.
My own situation is quite the opposite to dyslexia.
To change the subject slightly, I'm not dyslexic but I can totally relate to being bullied for being different, and being looked at differently at school.
I'm English, but I grew up in northern Scotland in Forres, and due to having a higher IQ than those in my year, I was put up a year, making me younger than everyone else in my classes.
Up there, people, especially the kids, are very proud of their heritage. So to have a weedy, curly haired English kid, with bottle top glasses and who's younger than everyone else is asking for trouble.
It took about seven years of constant bullying (physical and mental) both from the kids and even from the teachers before I snapped and fought back.
I still, to this day think about the suffering I was subjected to up there.
Ok, mine is being ridiculed and pushed around for something completely different to dyslexia, but, I think the situation of being ridiculed for being different to everyone else as a child certainly rings true.
Unless you've been through it yourself, you can never really understand how much it can hurt or how long it can last.
I was told by a friend of mine, a long time ago: "A bully only dies once. Those being bullied die a thousand times. So who is the better person for it?"