(James Yang/for The Washington Post)

Back to school used to be a time of excitement and anticipation.

Who would be my new teacher?

Would I remember my new locker combination?

Which electives would I have to choose from?

For a few weeks of the sweltering Indian summer, the academic future was filled with infinite possibilities. I’d lay out new clothes — different styles because I was convinced I would be a different person. I’d buy a new binder — the one with all the dividers because I was convinced I would be more organized. I’d vow to make new friends — popular ones because I was convinced the new and improved me would be in constant demand.

Then, somewhere between choosing my final college courses and packing lunches for my child’s first day of kindergarten, that magical feeling of boundless opportunities turned to expectation, obligation and competition.

I was suffering from back-to-school-induced parent guilt, and no matter how hard I tried to recapture the excitement of a fresh start, my mind and social media feed were filled with reminders of all the things I should be doing better. Like making creative Bento-style lunches with bite-sized finger-sandwiches fit for Marie Antoinette and veggies cut into easily stackable slices. Sounds simple, right?

Wrong.

I remember standing at my kitchen counter, a blood-spattered paper towel wrapped around the tip of my thumb, and glaring daggers at a pile of mangled vegetable slices. The sandwiches fell apart and the ­veggie-flowers had started to wilt. One unfortunate carrot-victim lay on a cutting board beside the world’s smallest heart-shaped cookie cutter. Except the carrot looked more like an anatomical heart, and the blood certainly wasn’t helping. Somehow my adorable garden-themed lunch had turned into a scene from a horror movie.

I cursed Pinterest for the idea, my kids for being fussy eaters and my fingertip for sticking out farther than I’d realized. But more than anything, I cursed myself for failing to live up to the idealized version of the super-parent the Internet and I both thought I should be.

And if guilt was my primary symptom, then the word “should” was the underlying virus chewing through my subconscious at an alarming rate. The more it replicated and spread in my internal monologue, the worse I felt. And let me tell you, parental guilt isn’t a fluke occurrence. It feels like a full-blown cultural epidemic.

Western culture has cultivated an idealized expectation that all parents should be caring, nurturing, patient and above all else, ­ever-present.

Researchers refer to this guilt-inducing trope of perfectionism as the motherhood myth or the goddess myth, though I believe it applies to fathers as well. Both are essentially describing the same phenomenon: unrealistic expectations accepted by parents who don’t have the experience or support to differentiate fantasy from reality.

Practically from conception, parents are bombarded with news stories and friendly advice telling them what they should and should not be doing. And if you don’t fall in line, you’re doing it wrong. The constant reinforcement that we are all relentlessly failing bolsters the unattainable standards of the perfect parent and forces us to continue to set goals we’ll never achieve.

Enter nagging, obsessive, gut-wrenching guilt.

Now, guilt isn’t always a terrible thing. Guilt is an emotion, just like anger or sadness or jealousy. Its purpose is to communicate to ourselves and others, and to nurture relationships with those we care about. Guilt often signals to us that we’ve harmed another person and drives us to repair that damage.

But guilt can easily be misinterpreted or internalized in a way that is not healthy.

I should be able to make my kids bento lunches every day, so if I fail, it must be because I’m lazy and don’t deserve a break until I get it right.

Guilt can also lead to anxiety, panic and further harming those we love. How many parents out there have yelled at their kids for minor annoyances simply because of stress? It’s an inescapable cycle.

So, if parent-guilt is evolutionarily designed to nurture and protect our children, how can we avoid standing in a puddle of our own tears at 10 p.m. before the first day of school, with a savaged thumb and a grudge against a smug lunchbox? There is a simple answer: perspective.

Just because something is “natural” doesn’t mean it comes easily.

We are all still learning how to be parents. Many new mothers have limited or no prior experience with children. As few as a hundred years ago, this would not have been the case. Humans were designed evolutionarily to raise children in small, collective groups. We evolved in communities that exposed us to child rearing from an early age and from which we receive constant support. However, with the widening spread of our modern cosmopolitan society, those familial, tribal groups have almost disappeared. But the instinct has not.

Instead we look to social media.

Unfortunately, the Internet is a vast one-way mirror leaving us feeling constantly like failures for not living up to the ideal person we imagine is on the other side.

But it doesn’t have to be this way. Instead of perpetrating the myth of the perfect parents, social media could provide a community — a village, if you will — that celebrates and encourages unique experiences and helps us realize that children don’t need us to be perfect. They need us to model for them how to thrive in the real world.

Acknowledging that we are all works in progress is probably the most liberating thing we can do. That we are still learning is a simple fact without judgment. Guilt is the feeling we have when we pass judgment, and it’s something that we overlay on top of the facts. Perhaps we could stop focusing on what we should be doing, and focus instead on what we are doing: growing.

Kids look up to their parents. If the model they are presented with is a spiral of unrealistic expectations and guilt, then that is the standard to which they will hold themselves.

One simple fix would be to eliminate “should” statements from our self-talk. “Should” statements have been found to increase anxiety, frustration and feelings of unworthiness.

When we use the word “should,” we’re not accepting reality. We’re talking about things that we wish were so, but aren’t (or vice versa). Next time you are confronted with the feeling of failure try using the discomfort to motivate rather than shame.

Let’s take my bento lunch example. It was easy for me to fall victim to the idea that “I should make my kids fun, healthy lunches every day.” Except, real life has a way of getting in the way, and more often than not I end up stuffing leftover pizza into a container alongside some Goldfish crackers and carrot sticks. Reality did not live up to the ideal. However, there are ways I could frame my guilt.

I could focus on the benefits of what I want to do: “I feel great when I get up early enough to prepare a balanced lunch for my kids.”

I could focus on how what I want fits into my value system: “It’s really important to me that my kids eat fruits and vegetables at every meal.”

I could focus on accepting and exploring the reality of what I’m feeling: “Okay, I’m feeling embarrassed by the lunch I sent with my kids today. I wonder why that is.”

There’s a fine line between inspiration and aspiration, and we are probably doing ourselves more harm than good by expecting perfection. Mothers already are goddesses. Fathers already are superheroes. The act of creating and sustaining life is what makes us divine. There’s nothing left to aspire to.

Eliminating the word “should” from our self-talk — even though it is hard to overwrite societal and evolutionary pressures — can be a rewarding way to start the new school year. A fresh start. A new you. Just like when we were kids going back to school.

And let’s be honest, we all fail. Over and over. But that doesn’t mean we stop trying. And no matter what the Internet says, we’re all doing great.

Mary Widdicks is a former cognitive psychologist, freelance writer and novelist. Her debut novel, “A Mutual Addiction,” will be released in January. Read more at marywiddicks.com. You can find her on Twitter @MaryWiddicks.