Poor mental health and mental illness are two distinct but related conditions that affect millions of people. According to Study Finds, poor mental health refers to the inability to adapt to life's changes, while mental illness refers to disturbing emotions that can disrupt daily life.

Both conditions can benefit from therapy.

Mental illness, also called mental health disorders, refers to a wide range of mental health conditions — disorders that affect your mood, thinking and behavior. Examples of mental illness include depression, anxiety disorders, schizophrenia, eating disorders, and addictive behaviors, the Mayo Clinic said.

A mental illness can make you miserable and can cause problems in your daily life, such as at school or work or in relationships. In most cases, symptoms can be managed with a combination of medications and talk therapy or psychotherapy.

Mental illness and poor mental health can get worse if left untreated.

According to USA Today, more than 50 million U.S adults experience some sort of mental illness every year. The National Alliance on Mental Illness (NAMI) adds that 5% encounter a more serious mental disorder.

Anxiety is the most commonly reported mental illness among U.S. adults, with nearly 1 in 5 (19.1%) affected. Major depressive episodes impact 8.3% of adults.

More than half of U.S. adults with a mental illness (55%) are not getting treatment, according to a recent study by Mental Health America. That's more than 28 million adults without the mental healthcare they need. Cost is a major factor for not seeking professional help.

Many people put off getting help because they think their problems aren't serious enough, while others get therapy because something in their lives isn't working, and they want to learn why. Some simply want to learn more about themselves and get help achieving their goals.

Experts say that therapy is a process that requires work on the part of the patient in order to succeed. You also have to find the right therapist, said Study Finds. Therapy can be expensive and frightening if you have to revisit a traumatic event in order to heal.

But Simon Sherry, a clinical psychologist and professor at Dalhousie University in Nova Scotia, Canada, says that even if now is not a good time to seek help, that doesn't mean there will never be a good time.

"If you don't want to start therapy, don't," he says. "However, it can be helpful to determine why you don't want to."

Some people are fearful of the stigma attached to seeking help for mental health issues, but Sherry said that people are more understanding than we anticipate.

"There's nothing wrong in investing in your health and happiness," he said. "If you're struggling with your mental health, know that you're not alone. Mental health issues are common. Having them or attending therapy does not mean there is something 'wrong' with you."

Here is a step-by-step guide that will help you find the right therapist.