Your wife needs to find different friends.
I don't care if he's only earning $30,000 a year -- no wife should be talking to her husband like that.
The problem that I've found is that most people live way beyond their means when they are selecting housing. This means that if you want to live with people like yourself, you have to too. If you spend what you should on housing, you end up "in a bad neighborhood".
So I feel like your wife has fallen victim to this problem. To live with the people she wants to associate with, she has to spend a lot more of your money.
You are in the top 10% of wage earners in the US.
It's a nice place to be. I make about the same and my wife treats me like royalty (and works herself and makes about 2/3 that).
If her vision of a "middle class lifestyle" is buying lots of shiny things, you're screwed.
Here are some links to make your wife feel better:
http://politicalcalculations.blogspot.com/2010/12/whats-your... http://en.wikipedia.org/wiki/Household_income_in_the_United_...
What has she achieved, besides you? The answer doesn't matter.
What matters is that marriage is an investment and you've both made a bad one. You both deserve better and will have to separate to get it, the sooner the better.
It won't get better.
It is very easy to criticize, if she is still believes you are an underachiever(you are not) Do what Fraajad says, let her find out how easy(or difficult) it is to succeed.
According to:
http://www.reuters.com/article/2010/09/14/us-usa-taxes-middl...
"Some academics divide the middle class into an upper bracket that includes professionals and middle managers who hold postgraduate degrees and often earn more than $100,000 and a less affluent lower middle class that typically has some college education with household incomes around the national median. Median household income in the United States was $52,175 in 2008, according to the U.S. Census Bureau."
It's also been shown that while happiness increases drastically up to 60k a year in annual income (in the U.S.A.), happiness does not increase further after that point. I.E. People making 100k are on average no happier than people making 60k, and people making 200k are no happier than those making 100k.