Venting place?

I dont know what to do.

Ok to start off I have ADD (Attention Deficit Disorder)
This is a mental illness... a disability. And recently it's gotten worse for me. A lot worse.
I feel as though I can't think. Can't function. Like my brain is shutting down. I hide things for no reason- or BC I think I'll get in trouble for eating something or feel guilty for eating that thing. It's like no matter how hard I try... I can't do anything right. Idk why. I don't want to be like this. I don't want to be the person I feel that I'm becoming. I feel like that's out of my control though. For a couple years it had gotten Better. I wish I had stayed like that. I just don't understand... why me? Why do I have this terrible disability? Why am I unable to think. To remember things. To function? I've cried so much lately. I'm crying as I'm writing this.

My mom has told me to go on medication for this but idk that I want to. I've heard that these medications completely change your personality and I don't want that to happen. But I also can't keep being strong for much longer. I just can't keep pretending that everything is alright. Idk what to do.