Atheists don't get divorced because they're amoral starfishs who consider the law the only restriction on their life and sometimes not even then. Okay, obviously that's not what you meant, but their morals aren't the reason they stay married less frequently. It's just that there's a higher stigma around getting divorced in religious communities. Though honestly I'm surprised atheists who don't take marriage as seriously still get married at all.
Sure, spend some money on it. A month or two's wage perhaps, but don't blow all your money on it.
Two months wages is a loving lot.
Maybe not if you're a part time fry cook getting married while still in college, but for anyone at a point in their life when its reasonable to get married, that's still potentially ten thousand dollars.
By the way, my mother has been divorced twice, and my father has been divorced three times.