With SlutFest 2009 (read: Halloween) nearly behind us, a string of warm ‘n’ fuzzy holidays await. It’s during this magical time of year that I normally scour the Web for evidence of humanity’s altruism. But, sadly, with every holiday miracle comes a crime report featuring an everyday psychopath to steal old St. Nick’s thunder.

Leading off the season, we have a newly dumped Portland misfit who broke into his ex-girlfriend’s house to beg for another chance. After her immediate rejection, he pushed her against a wall, whipped out a knife and stuck it to her tiny pet fish.

In case you didn’t learn your lesson from “Fatal Attraction” (the ’80s thriller in which Glenn Close boils her ex-lover’s pet rabbit in a jealous rage) don’t let this happen to you.

It’s tougher than it sounds. The world teems with those obsessive Facebook stalkers who just happen to glance at a Friday night dance party you’re attending and — by sheer coincidence — rain on your bump-and-grind parade.

But hold your judgment a quick second — we’ve all been that jealous dumpee at some time. One day you’re in your boyfriend’s delicious BMW, surveying all the poor single people trudging to the shuttle stop, and the next day you’re alone with “Tyra” and a silent phone, asking Ben & Jerry what you could have possibly done to deserve this.

It bites to be left in the dust, but after a few weeks as the stereotypical, See’s box-throwing dark princess, you too can bounce back.

When the tables turn, however, and you become the dumper (aka heartless bitch), it’s easy to shrug off that miserable abyss you’ve pushed your ex-lover into and jump back into the brawny embrace of college singlehood. For me, Christmas came early last year after my breakup: two apartments full of frat-guy testosterone moving into our hallway. Deck the halls, baby!

But if your ex’s pathetic cries are still drowning out the silver bells, it’s time to pull the plug on those weekly sympathy heart-to-hearts.

Acknowledge that you’re the reason for his bucketful of tears — if you seem oblivious to your ex’s pain, he will do everything possible to drown you in it. But also recognize that you don’t have to hold his hand while he’s dabbing his tears — that’s in his mom’s job description, not yours.

While the bloody goldfish made it stupidly obvious that our aforementioned Web felon’s deranged behavior screamed “restraining order,” it might not be so crystal clear when your average ex has crossed the threshold of obsession. After all, this is a person you presumably felt some scrap of a feeling for at one point. It may be difficult to recognize when he’s truly jumped off the deep end.

But take the time to look a little harder, folks, and really try to discern those warning signs. Because discarding that old, worn-out battery before it becomes a toxic pool of acid can save you a whole lot of cleanup time.

Note that the fish-mauler from our Web story released a post-crime statement saying, “If she can’t have me, she can’t have the fish.” By the same logic, a psycho ex can — and will — try to sabotage your chance of reeling in another lover.

The classic example: personal jabs made in public. Last year’s ex pulled aside my best friend and told her he can’t even believe he liked me because Hispanic girls aren’t his type.

I mean, premature balding isn’t really my cup of tea either, but you don’t see me whispering that into his best friend’s ear.

Kindergarten-level racial slurs and other playground jabs reveal that your ex is lacking something key in the post-break-up rehab process: Pride. If he’s not even bothering to preserve his good-guy image, he’ll do anything to hijack your attention. It’s a surefire indicator of his quest to tarnish your image so that you appear unlovable to anyone who’ll listen — because after all, if he can’t have you, no one should.

So when he starts pulling the race card and you — still trying to be sympathetic — haven’t done the snip-snip yet, remember that when kids act their naughtiest, it means they want love and attention. Which isn’t your problem.

These blips on your lifeline, you must remember, are big boys. So go ahead and get it all out in one — I repeat, one — conversation. Anything more will only satiate his ever-burning desire to keep you in his life.

Commence silent treatment.

This is especially hard for people who have Snow White’s desire to befriend all fellow humans and cuddly animals (example: me). But fish-killer has a valuable lesson to teach us all: The frogs you kiss before arriving at Prince Charming’s castle will amount to an eternal buzzkill if you let them stick around and make you feel guilty. However many sweet-talking apologies escape your lips, they’ll only fall on seething, deaf ears.

The next time a breakup goes awry and you have to pull a disappearing act, remember: It’s for your own good. No one wants to get chewed out for talking to the hot neighbor or not responding on Facebook chat. To a scorned lover, everything you say will always be wrong, nothing you do will ever be right and no one you date will ever live up to his glorious precedent.

So when you see that drunk dial coming in, do yourself (and your Kleenex-chaffed ex) a favor and let it go to voicemail — life is too short to let the frogs overstay their welcome.