Marraige and Taxes

So, there's an article I read on AOL, (From USA Today) and the title read: AOL News - Divorce Drops, Along With Marriage The article caught my eye, because I am not married.
Brian and I have been "co-habitating" for about three years. My two boys and his two boys and one girl live with us. We've considered marraige, quite seriously, off and on since we moved in togehter. We both strongly believe in marraige, and want to be married. The report says that we fall in the 40% of couples who have kids and live together, part of a growing trend that suggests that the divore rate is dropping, but mostly because people are simply chosing to live together rather than marry at all.

The article doesn't go into why, perhaps, marraige is in the decline and cohabitation is on the upswing. It does mention that it's not a good thing for the kids, which I can believe.
For Brian and I the reason we haven't married is simple economics.
We both live so close to the cusp of "getting by" that every dollar counts. And we frankly can't afford the tax penalties of marraige. What we'd lose, in both taxes and benefits for our kids through the school system and the state, is not worth making it legal.

We went to an accountant a year or so ago and had him help us calculate what we'd lose, gain, and break even in. Getting married would cost Brian and I almost $5000 a year (rounding it off) and for a family our size with our income, that's devastating.

Sad, isn't it? We have a government and an administration that supposedly supports marraige and morality, families and children, and ecomomic growth. But the marraige penalities and costs of the same make it difficult if not impossible to hang on to what you have if you decide to "make it legal".

Our family is okay. Brian and I share so much love, and the committment is there even if the document isn't. Our kids know it, and so they have the security of a family, whatever the legal letter says about us. I'd like to think we were a better model for them, I'd like my children to marry rather than live together. But perhaps if they lear to commit, and stay committed, it is enough.

I don't see tax law changing any time soon, and I suspect, as the article says, that co-habitation is here to stay.