I've been pretty under the weather the past couple days (down with the flu), and having to deal with people that are supposed to be older, wiser, more experienced than me but with a low EQ is driving me insane.
It's OK to vent, if it's to the right party, if you know you have pull with the other party, and you won't appear insane to the other party. Those are just the basics. It boils down to interpersonal skills, which is absolutely the most important thing in business. Successful people aren't only smart, they know how to use their interpersonal skills/pull/connections to make things happen. Stop wondering why people who don't seem as capable get to the high positions in a company, because they had the other side of the equation: people smarts.
I've always approaches situations like this analyzing each parties interests; make sure everyone's interests are laid out on the table and don't play telephone - ie. don't call me, tell me one thing, and then call the other party telling them another - if you end up doing this you are just making it tough for yourself.
Just let me know what you want; surprisingly most of the time people just like to whine and complain but are not sure of what they want as a result. So why are you complaining?! Is the result that you propose the best for the company or the best for yourself? Are you trying to convince your boss to side with you? if that's the case then you better not propose the case where it's best for you, because your boss would see right through that and end up re-evaluating your EQ - which is exactly what I've done. Ta-da.