Roughly 80% of the Democratic Party is going to show support for Netanyahu here, and it's since become clear that it's Boehner who holds the blame for breaking protocol, not Netanyahu. The only person who has the ability to destroy the "special relationship" is Obama, with heavy-handed punitive steps that would ring bells that can't be unrung.
What heavy-handed punitive steps has he taken? Please don't act as though Netanyahu is blameless and merely ignorant of the workings of American politics. Netanyahu lived and worked in the US for several years. His current and most recent ambassadors to the US are both former Americans themselves. Bibi knows very well what the ramifications of this are. He could have declined. He could have suggested the speech happen at a later date. He did none of these things.
He hasn't. Ergo, the relationship isn't destroyed.
There's clearly a deep personal dislike between these two leaders. However, despite the occasional wildly irresponsible suggestions from armchair pundits and even the occasional Obama adviser, Obama hasn't escalated the tension in ways that would cause permanent damage beyond this administration - IE, using the UN as a cudgel.
Yes, Netanyahu could have denied the speech, and might have if he had been informed by Boehner that this was without Obama's knowledge. But he wasn't told that at first, and he likely found out about it from Obama's over-the-top reaction. Once that happened, to back down would make him look cowed by a President who is less than popular in Israel.
Plus, to be blunt, I am REALLY unsympathetic towards any complaints about protocol violations from a President who unilaterally declared the Senate in recess so he could make illegal appointments.