Having a physical disability can be hard sometimes but you can explain to people how to help you or you know what works for you.  A disability that can be seen you are able to teach others and also bring awareness to it.  But a mental illness is not that easy to explain.  Here is a reason why I think it’s harder to tell others about mental if you have depression or some kind of mental illness;  I think people think it’s all in someone’s head that you have depression but as I read more about mental health is not just in their hands.   Sometimes it is something that they can’t control or even something from their past that has left hurt that they don’t think they feel they can let go of.  Or maybe that is just a disability.   This article about someone who is sacred to tell her story just because others don’t see that having a mental illness is a disability.  https://themighty.com/2017/05/scared-my-mental-illness-makes-me-hard-to-love/.
This is one reason I want to help people who feel like they can’t talk about mental health.