This started off as a commentaire to Shikabane-Mai’s pick (“Episode 6 is an emotional episode. Will this be why House and Cuddy kiss?”) and then it got completely out of hand in terms of length and scope so I decided it was plus appropriate to re-write it as an article! Feel free to contradict me, I l’amour debating!

Back in season 3, when asked on the possibility of a relationship between House and Cuddy, Katie Jacobs answered that there might be “a moment of weakness”.
To me, it’s like saying House and Cuddy are like candy: toi know it won’t do toi any good but despite your efforts to be reasonable and discipline yourself, there’s bound to be a moment when toi let yourself go and indulge your craving. Because, however painful the consequences, Candy is delicious!
The question is, why now? After all, the attraction has always been there. Maybe it has become slightly plus pronounced in the last season (I’m thinking Catholic school girl outfit and lap dance!) but if par “moment of weakness” Jacobs meant “a one night stand”, there would have been plenty of other opportunities.
The answer is that of course it’s not only about the sex, and the weakness in question is less to be understood in terms of lust and libido, than in terms of emotional vulnerability.

First, the lingering sexual tension between them has been addressed before, plus specifically in season 3, montrer House as the one stepping vers l'avant, vers l’avant and testing the limits of their relationship, and Cuddy as the annoyed yet clearly flattered recipient of House’s attentions. The flirtatious dance culminated with the somewhat expected revelation that those two had played naughty at some point in the past and the argument ended with Cuddy implying that, despite the undeniable attraction, she did not consider House as serious dating material: “Wilson is a sûr, sans danger choice” (“Act Your Age”), meaning that House, on the other hand, is relationship hazard. I partially believe House when he a dit that asking her out was only a test: at the time, it was enough for him to get confirmation that she wasn’t immune to his charms and that he still had some sort of power over her. I’m convinced neither of them was ready to act on whatever feelings they had for each other.

Then season 4 cast a new light on their relationship. It’s been made plus explicitly clear that not only do they not hate each other but there’s actually a deep current of trust and affection between them. In other words, it showed the groundwork on which a real grown-up relationship could be built.
Also, season 4 has shown Cuddy gradually acknowledge to herself that she cares for House plus than she’s willing to admit, and – and this may prove to be a real stumbling block in the future – plus than she should allow herself to as House’s boss and sounding board (the events in “Living the Dream” represented a cornerstone in that process). This is very important in the advancement of their relationship because, as rive (was it Jacobs again?) pointed out, she’s the one in control in their personal relationship. House only gets what she’s willing to let him have, hence his frustration:

“Your mind convinced your body to get a rash, photophobia and vomit. How d'you know it wouldn't have shut down your cold, cold cœur, coeur next?”
“I don’t owe you”
“You’re mean”
(“Airborne”)

Whatever his reproach to Cuddy, House is no plus spontaneous than she is when it comes to displays of affection. He’s of course very good at keeping his feelings at bay. Cuddy much less so, but although her emotions are easier to read from the outside, she’s still at least trying to keep them under control. House and Cuddy may have a different take on relationships, but at the end of the day, they are both emotional cripples that built a mur around them, a protection that turns out to be also a trap.

Yet that is precisely what has started to change, especially since the events in “Wilson’s Heart”. They each had their own epiphany: he admitted he didn’t want to be miserable and feared being abandoned; she realized what it would mean for her to lose him. Cracks are appearing in the wall.

So far, they were stuck in a mockery of courtship, a routine as old as their relationship. And as sexy as the banter, the flirting, the games and the fights are, they were never of real consequence. Now, don’t get me wrong, I don’t want them to lose that dynamics of theirs, but I also think that to be really united, they need to let go of the protective layers of sarcasm. The problem is (at least, it appears to be a problem for House), being plus explicit also means being plus exposed.
I think one of the reasons Cuddy harassed House into talking to Wilson in “Dying Changes Everything” is also because she hoped Amber’s death would make him realize, perhaps as she did, how important it is to make sure people know what they mean to you, to explicitly tell them how toi feel before it’s too late. And if House can do that with Wilson (and he did in the end), then maybe he can do that with her too.

“You’re willing to risk your career but you’re not willing to say you’re sorry?”
“I told him I’m sorry. He didn’t believe it.”
“Well, make him believe it!”
“I don’t believe it.”
“You don’t want to believe it! Because if toi tell Wilson how toi actually feel, about him, about what happened to Amber, about your part in what happened, and he walks out the door anyway... If toi make yourself vulnerable for once in your nerve deadening, emotionally obliterating – You’re doing the same thing he is! You’re running away!”

Echoing House’s words in her performance review in “No plus Mr Nice Guy” (“What toi want, toi run away from”), Cuddy has turned the tables on him and she’s now the one urging him to take a chance and “do something”. It seems to me that somehow, in the aftermath of the events in “Wilson’s Heart”, she has gained plus confidence in her relationship to him whereas he’s experiencing being plus vulnerable, and of course, has problems adjusting to that new situation. For once, Cuddy asked permission to come in, only this time, House wouldn’t let her.

So to answer Shikabane-Mai’s question (finally!), I would say that yes, maybe tragic ou “emotional” circumstances are what it takes to pull down the remaining bits of the Great mur of China between l’amour and hate. Because they’ve known each other for so long and there’s history between them, they will always be self-conscious around each other, unless they’re caught off guard, in a moment of uncalculated emotional vulnerability. And that emotional vulnerability will partly be caused par exterior circumstances, but I hoped I’ve proved that, far from being a mere impulse, it’s also the outcome of a long and complicated process.