Why can people be diagnosed of more than one mental illness?

Like I have bipolar, BPD and eating disorder, I really want to know how to gradually get over it because it's really tiring and overwhelming and although I do educate myself on them, still feel I need therapy sometimes..
Asked by Dbririminaj

Mental health is a confusing subject area, sometimes! People can have 1, 2, 3, or more diagnoses, but all would be accounting for a different branch of what's going on with that person. A lot of symptoms overlap, yes, but each diagnosis is unique in its own regard. You mentioned that you have Bipolar Disorder, BPD, and an eating disorder. Those sound accurate in their diagnosis, given that each is in a different area of mental health, as well as each separate in how it presents. That being said, it does make living difficult sometimes, having several diagnoses. I'm sorry that you struggle with those and I'm sorry to hear that you often feel tired. I don't blame you -- it's difficult to wrestle with yourself all of the time. That being said, it is possible to live a life that you're comfortable with. Some diagnoses are simply there -- thanks, genetics! Bipolar Disorder is probably something that runs in your family, which declares that the diagnosis is NOT YOUR FAULT. Is the diagnosis unfortunately your responsibility to manage? Yes. But it was never your fault in the first place. Medications, reaching out to your positive supports, and reaching out to professionals can all be exceptionally helpful in battling the symptoms that make your life difficult (i.e. mood swings, your ups and downs, feelings of emptiness, etc). Don't hesitate to reach out for support -- it is so necessary for the proper treatment of things like this. You are strong -- you have made it this far! Asking for help can be really difficult -- one of the toughest things in the world to do. That being said, no one was meant to navigate life alone let alone a life that is riddled with emotional difficulty. Identify who your biggest supports are -- the people that help you to feel safe -- and reach out. Your diagnoses can certainly be managed and your life can certainly become more comfortable, but don't be afraid to lean on others in order to beat that tiredness. With hard work and treatment, your diagnosis of an eating disorder can be placed in the status of "in remission," which is when you cease to display the symptoms of that disorder (including the distorted thinking patterns). Bipolar is something that you'll likely wrestle with forever, that that doesn't mean you can't live your life comfortably -- it is possible to have this diagnosis, while also living comfortably, but that's possible through treatment. BPD is likely a result of some difficult things you've been through -- it is generally a result of some sort of trauma. I'm sorry that you've endured something difficult, albeit I'm assuming, but those things will need to be addressed in order to help you move past some of those traits of BPD that make your functioning more difficult (i.e. having stable relationships with others, any level/type of self-harming behavior, etc). I urge you to reach out, because you're worth that! You deserve a life that is comfortable -- a life that isn't so tiring. You aren't alone -- help is here. Reach-out. Grab that life you deserve and enjoy the life that you've created for yourself.