Admit it: sometime, against your better judgment, you root for a celebrity. And then they release a single. Or a racial slur. Or a political endorsement. Or a comment about homeless people's style acumen. And ladies? That's a dealbreaker.

Unless we are mentally ill, most of us are not under the illusion that we are going to become romantically involved with the stars we like. Maybe we like to look at them, or enjoy their vocal stylings, or appreciate their interpretations of good scripts. Sometimes a secret part of us even thinks we'd maybe sorta-kinda be friends and could collaborate on some really good work! But for the most part we understand that they are public figures and perfomers whose professional lives have very little to do with their realities. That said. Sometimes something happens to end a celebrity like-fest, and it's over. There are certain things that cannot be tolerated, even in a pretend, quid-pro-quo relationship. Unless one is a professional train-wreck (see: Courtney Love) or teflon-coated (see: Alec Baldwin) these tend to be a few of our top deal-breakers:

1. Racism, Bigotry, Homophobia and General Hatefulness. Okay, as these things go, this is by far the most legitimate, as well as the most off-putting. When we hear that an actor has been using gay slurs on set, or has a penchant for drunken anti-Semitic tirades, then, yeah, that's not someone whose career, money-making or continued presence in the public sphere you want to encourage.
Case Study: Jonathan Rhys-Myers. While the intense blue-eyed faux-Tudor bewitched many, reports that he'd tossed the N-word, as Dodai says, "broke my tiny gin-soaked heart."

2. Scientology. Whereas breaking up over bigotry is defensible - necessary, even - the Scientology deal-breaker is somewhat problematic. What does it really matter, after all, if an actor you never meet whose work you've enjoyed on that stylish cable drama believes in a New Jersey-born religion that involves Dianetics and alien life? It's not like most of us think it has powers more sinister than getting celebrities to fork over a lot of money. And yet, somehow it serves to sever the small pretense of normalcy that makes stars relatable.
Case Study: Beck. When he rejoined the church of his youth, many of us mourned. How could someone famously irreverent be irreverent after that? Someone asked me if I thought it was ameliorated by the fact that he'd been raised in the Church of L. Ron. My answer to that is simple: plenty of people have abandoned other religions and not looked back — religions, by the way, that don't involve Celebrity Centers, bans on psychiatric drugs and women being silent during childbirth.

3. Bad Company It is disconcerting when one reads that the dignified elder statesman of the British stage who's played Merchant-Ivory roles with such sensitive gravitas regularly goes trolling for women with former U.S. Presidents (Anthony Hopkins, ahem). But this was nothing to the disillusionment that greeted the mile-long list of signatures in support of criminal sleazebag auteur Roman Polanski. All we were asking for here was that people not go out of their way to support an objectively bad cause! Too much to ask.
Case Study: Emma Thompson. Et tu, Emma? many of us wept when we saw this former stalwart of the smart set sign her name to the infamous Bernard-Henri Lévy Polanski-support petition. I mean, we expected this kind of thing from Woody Allen, were saddened but not shocked by Wes Anderson, disappointed by Tilda Swinton, but Emma?! Although she later recanted, for some of us, the spell was broken.

4. Dubious Political Statements: While "asinine or oblivious statements and tweets" generally could be a category all its own, few things have the alienation power of the political stand. Be it that aging legend who campaigned with Palin or the Oscar-winning intense person who knows the soul of Hugo Chavez, be it via Twitter or interview, it's rare that an entertainment celebrity's public image is burnished by a foray into politics. Afterwards, it can be hard not to feel like you're tacitly endorsing a cause not of your choosing.
Case Study: Scott Baio. Need we say more?

5. Terrible Vanity Projects: Used to be, being an actor — a star, even! — was enough. Maybe they had directing ambitions, at most. Not anymore. Now, every brooding handsome person has a dubious band, every starlet a record deal, and a few cover Tom Waits. (The exception, of course, is Franco, whose random forays have only served to cement his reputation for...well, we're not sure.)
Case Study: Zach Braff. First, he was just the mildly amusing schmendrick from Scrubs. Then he showed us his soul. And it was a cliche.

6. Rumors of Dickishness: It's kind of heartbreaking to hear that this nice-seeming TV host was a tyrant to that friend of a friend who interned on the show, or that that married star hit on somebody's sister in a really sleazy way this one time or that the down-to-Earth-seeming rock star was a total diva who stiffed your neighbor's cousin the time he waited on him. Then you always have to act like, 'oh, well, I assumed he was a jerk but I like some of his work.' The only consolation is the power to pass those rumors along.
Case Study: Well, that would be spreading gossip.

7. Cheating: Jesse James recently described himself as "the most hated man in the world," most of us thought you wish. But if James had had millions of rabid fans, chances are this would have put him on a global-hatred level. We all fall for the storyline, and much as we might play at sophistication, most of us are put off by the confirmation that yet another star is, in fact, just a typical jerk with a good PR machine. And we've been had.
Case Study: Tiger Woods didn't just play Elin for a fool — we were all taken in, even those of us who might have said that we assumed the worst of everyone. And for this we cannot forgive him.