How do you accept that you have a mental illness and accomodate the illness without letting it define who you are???

I know I have a disorder and I have made life changes to accomodate it but it upsets me that I have had to do that and can't be a regular, "normal" person and right now I feel like the illness is controlling me. At what point do I take control back and not let the illness play such an important part in my life????