I must quite agree on the divorce thing... I think they're most likely separated at home... something isn't going well between them, they seems both sad, depressed and tired... they meet in random places by case, don't really search for each others... especially House... he's freeze after the apologies and the admission of care in SoaCG...
I hope the authors will fix their relationship very soon 'cause the whole show is suffering for it...
But I think there's still chemical between HL and RSL... they act together too well... but I think the feeling they have to explain now is just this "separated at home" feeling... that I hope will be explained and fixed later...