Mental illness is a mental ‘issue’ that many people don’t fully understand or may not understand at all. Some illnesses make you panicky, A few can make you sad or upset for no reason. And others might cause you to have mood-swings, have a hard time focusing on anything, or even something particular. It might make someone repeat an action/thing over and over again without satisfaction until it’s ‘right’. There are many different types of mental illness: different subgroups inside certain illnesses that sometimes connect with another mental illness or more.