Depression is not just feeling sad or blue. It is actually a medical term. It is an illness. When we have depression we can't just "snap out of it." It isn't a choice.
I personally have had episodes of depression since I was 11 years old. I first began medications and therapy for depression at age 19 and still utilize both meds and therapy today.
Here are the symptoms of depression according the DSM-5 (the book that doctors use to determine if a person has a diagnosable mental health condition):
Five or more of the following symptoms over a two-week period
It is most important that you understand that Major Depression is an illness, not a weakness of character. No one would choose to be depressed if given the option. However, that does not mean you have to be stuck with this illness indefinitely.
Research shows that the combination of therapy and medications is the gold standard for how to treat depression. If you or someone you love is depressed, it is important to receive professional help right away. Without the right treatment, depression can worsen.