Maybe this is all Andy Murray's fault. So often over the past decade has he made the impossible real, against all precedent and logic, that you never wanted to give up on one final sweet miracle.
It won't happen. This is not the end, only because the end has been in progress for a while now - since his first hip operation a year ago, through the painful and truncated comebacks, every time he has limped along a baseline between points like a man twice his age and with half his physical gifts.
You don't want to believe it's the end because it still feels so early. Murray is 31. Roger Federer turns 38 in August and goes into the Australian Open looking to win his third title on the bounce. Rafael Nadal went through a three-year period where he failed to win a Grand Slam, has suffered with knee problems throughout his career and recently had ankle surgery - yet still the sensible expect him to win in Paris come early summer.
Murray's tears in Melbourne on Friday told a different story. Maybe his body will hold up in his first-round match against Roberto Bautista Agut. Maybe he will even beat a man who beat Stan Wawrinka, Novak Djokovic and Tomas Berdych to win the Qatar Open last week.
Even if that comes to pass - and only the sentimental and speculative would wager much on it - it changes almost nothing. "If" became "when" a long time ago.
There will be more tears on Monday but it should also feel like a celebration. Murray has been one of the special few who created a dizzy golden period for British sport that took the old cliches of plucky defeats and oh-so-nears and submerged it in a flood of ludicrous success: successive Olympics awash with golds, fourth in a medal table, then third and then second; a British man winning the Wimbledon singles title, a Briton winning the Tour de France, those grails repeated and made commonplace.
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For a man who at the start of it all seemed shy and reticent until the point he was angry and frustrated, Murray almost always took you with him.
In the early disappointments, including four defeats in his first four Grand Slam finals, you felt the same mix of regret for what might have been and hope for what still could be.
On Wimbledon's Centre Court, where he suffered death by tie-break to Andy Roddick in 2009, where he was overwhelmed by Nadal in consecutive semi-finals over the next two years, his tears in defeat by Federer in the final of 2012 triggered the same response in many watching helplessly. It was never going to happen. The rest were just too good.
Until they weren't. Murray's storming run to Olympic gold on the same court a month later encapsulated what that giddy fortnight in London did: it made you a believer, made you bowl about the warm streets with a grin on your face, made you lob the old preconceptions out of the open window.
Doubt was still part of it.
As Murray went two sets up in the US Open final that September only for Djokovic to rapidly bring it back level, a late-night thriller from the city that never sleeps had Britons chewing the edges of their duvets.
Even the presence of James Bond in his corner made it no easier to watch. British actor Sean Connery might have whooped and grinned his way through the contest but for most of his compatriots the four hours and 54 minutes until a tired Djokovic backhand return dropped long were somewhere between beautiful dream and dreadful torture.
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An easy New York cliche would tell us that if Murray could make it there he could make it anywhere.
It didn't feel that way on Centre Court on Sunday, 7 July 2013. People had lived and died waiting for a British man to win Wimbledon, and many more were close to the edge in that last excruciating game.
Murray was leading 6-4 7-5 5-4. He was 40-0 up. And on serve. First one championship point was lost, then another, then another, then three break points for Djokovic.
You can't forget these moments, not when you have gone through them with a sportsman. And when Djokovic's backhand into the net ended it, after 77 years of waiting, no-one knew quite what to do.
Murray put his hands to his head. His legs went. He booted a ball into the crowd and fell over and cried. Around the country millions were doing the same and more.
That would have been enough. Except there was so much more, the bewilderment now coming from the fact a lot of what was to come wasn't even that anxious.
Murray's second Wimbledon title was a fortnight of total control, sport as a nerveless execution. You could almost enjoy it. You could almost relax.
The implausible no longer had the same power. A first Davis Cup triumph for Britain since 1936? Why not? Becoming world number one, in the most competitive era of all, when Federer, Nadal and Djokovic were stockpiling Grand Slam titles in an unparalleled arms race? Of course.
It is one of the melancholy truths of sport that only a few of the greats get to retire on their own terms. Even the strongest, the most tactically astute, are overtaken or outshone in the end.
Murray wanted longer. Some of his supporters will still be in a state of partial denial.
None have been short-changed or cheated. Murray's successes were never preordained but were the culmination of a lifetime of relentless work and ceaseless ambition.
It took him eight attempts to win Wimbledon, four semi-finals to make the final, another to finally step onto the summit. He won Grand Slams for a country that had long ago forgotten how to. He began as an awkward, gawky teenager and ended by winning BBC Sports Personality of the year three times.
This is one ending. Murray will be remembered for another: standing under a cloudless July sky six years ago, arms aloft, a famous golden trophy glinting in the warm summer sun.
In an era of special sporting memories, that is one to keep you warm long beyond this grey winter.