America is the land of dreams. But not all aspirational dreams are good for you. Unattainable dreams are toxic. The test is simple: if a dream serves up more tears than champagne, it’s a party pooper. I found no manual for how to kill a dream. So I decided to write one.

It is surprisingly hard to rid ourselves of unattainable dreams. They feel like they are an intrinsic part of the self—but they are not. A dream is a staunchly held collection of ideas about ourselves and about the conditions for our happiness.

An unachievable dream is just like unrequited love. By definition, it will bring you more longing than happiness. When you have a dream that doesn’t love you back, you have a stark choice: you either bury it, or you risk being buried with it.

If you decide to kill a dream, you may well have to do this on your own.

People only want to hear about your failures if you ultimately succeed. They will rally for you when you dream big, but they find it uncomfortable to watch you capitulate. Even therapists can lobby too hard for their patients’ dreams. In our “I have a dream” culture, there is no place for “I once had a dream—and it almost killed me, so I killed it first.”

It helps to tally the other dreams you’ve had in your life. How did you miraculously achieve those? There was hard work and perseverance, sure, but also luck, that beast no one can control.

I have achieved four out of the five dreams I’ve collected, including “the California dream.” Not a bad statistic. Perhaps it was greedy wanting a fifth and last dream. It is often this last dream, when unrealized, that starts infecting our enjoyment of those dreams already achieved.

Dreams shine so brightly in the psyche that there is a horrible darkness when they are dismantled. Dreams are hope, and we need hope like air and water. How do we ease this necessary eviction of a hope that has turned hopeless, a star that has become a black hole?

I found solace in observing and admiring those who knew when to let go—and who, in so doing, have brokered precious peace of mind for themselves.

Everywhere I look, people have had to mourn long-cherished dreams. Many friends had come to terms with the idea that they may not find “the right partner.” Others had given up on ever having a child, or having their healthy body back, or landing their dream job or career.

The world is full of admirable people who successfully put their unachievable dreams to rest—and who moved on without torturing themselves or others. We call it “graceful.”

Then there are those who grasped at their wretched dream till the end. They are consumed by it, decades later, still bitter and angry and depressed. One friend strived to become independently wealthy like the crowd he frequented. But it is not easy to become a human ATM. Failing, he turned to alcohol, which then led to the loss of his career and marriage; a case of an impossible dream shattering those already earned.

Another friend could not let go of her dream of having three or four kids, and in the process, was neglecting her husband and healthy child. Many parents harbor vicarious dreams about their children (what they could have become, whom they should have married, where they ought to live) straining the relationship all the way to the grave.

At what point does grit become a stubborn refusal to accept reality?

Letting go of unrealizable dreams gracefully is an important life skill and should be encouraged. Fruitless perseverance for years, decades, or for life is no longer the pursuit of happiness, but of the impossible. It is chasing the perfect life that does not exist.

Perfection is the enemy of sanity. Perfection kills all that is good enough.

An extremely successful friend once said, “The world is not your oyster.” It seemed like an odd thing coming from him, then years later, he died young. Letting go of a dream is a glass-half-full kind of task: it involves gratitude and acceptance of the imperfect self that is living the imperfect life, in an imperfect world.

There is no clear warning when a dream turns lethal. It’s easy to convince yourself that you need more time and more effort, or that you’ll get lucky next time. But luck is known to take long sabbaticals. Your emotions will tell you. Does your dream still give you a spring in your step, or has it turned into a ‘dementor,’ depleting your soul more often than not?

My tennis coach once said, “Never change a winning strategy, but always change a losing strategy.” I found it is a good rule of thumb to think of a dream as merely a life strategy that may or may not work, a process rather than an outcome. Notice how it is liberating to say that becoming CEO or prima ballerina is not a dream but a strategy and that the final outcome is “happiness or pride or peace of mind.” That final outcome can then be reached by means of a different strategy, such as becoming or doing something else.

Just as you abandon a failed strategy, if a dream turns dark, bury it in the dream cemetery. Everyone should have one in their backyard. If you can’t bury it, park it somewhere for a while and let time work on it. A parking lot is just as good as a cemetery. Free yourself. There are many other dreams to be had—including the ones you’ve already attained but forgot to enjoy. And if you are too tired to dream big anymore, help someone achieve their own dream. That is a guaranteed joy like no other.