The phrase "difficult period" refers to a challenging or hard time that someone goes through. It can describe a period of sadness, hardship, or struggle in a person's life. Full definition
He specializes in helping people work through difficult periods in their lives. (psychologytoday.com)
Anxiety may also be used to describe the intense worry and fear that may come up during difficult periods of our life. (rbboswell.com)
You may have been through difficult periods in your life where your primary goal was to keep a roof over your family's heads and food on the table. (collegerecruiter.com)