If something is durable, it’s meant to be reliably stable for a long period of time. It lasts, and it lasts despite wear and tear. If you are comfortable in your day-to-day, then you’ve build in some durability into your life.
But durability has its limits. Replace regularly scheduled school and work with a social-distancing-required isolation with no clear end date, and you have stretched your life’s routines beyond their durability.
It’s going to take some time, and some patience, and some creativity to find new durable routines that work. Don’t expect too much of yourself too early. Go easy on yourself. You’ll get there.
It will be hard but you’ll get there. Your core, underneath it all, is also durable.