I wanted this to be formatted so I posted it here instead of in the comments.
Did you know that marriage as the final step in a relationship has been embedded in the industrialized world to the point that couples feel obligated to get married despite not wanting to get married or not being ready to? After divorce was made more accessible marriage became even more of just a symbol of the social structure rather than something all couples that were married wanted to be in.
As it became easier to get in and out of marriage, while it carried the weight of social expectance, it didn't carry as much legal weight. If you felt like getting married you did because divorce seemed easy. Divorce may not be something you wanted but it was an easier option than it had been in the past even though divorce still holds stigma against those who say they are divorced as it implies failure, foolishness, or recklessness.
We are able to say divorce rates have gone up because divorce is a more accessible option now that was decades ago. Marriage rates are falling as the social stigma against people who aren't married falls. As it becomes more acceptable for couples to be life partners without the legal aspect or the social expectancy of marriage if that isn't what they want. As time goes on and society allows for more public honesty when it comes to what couples want and don't want and as the prices for the weddings that come with marriage get higher and higher, we are seeing that marriage is regaining a new definition in the hearts of couples and as such it has become a more selective thing.
Marriage used to be contracted between two families for power and social status regardless of the couple's love for one another because that was not the original intention of the concept of marriage. Then it was romanticized so everyone wanted it and everyone, especially women, were expected to have it however it still retained the same social status weight with a lighter emphasis on the power aspect of it. Then divorce became more tied with the idea of marriage and not just something that floated around for special circumstances. This allowed people to engage in something that still had heavy social status but with an accessible out. Then people got sick of the social expectancy that came with dating and love because it always had to end in marriage.
Now it is morphing to adopt a new way to see it, something couples can consider if that is how they want to celebrate their love for one another. Not a necessary thing but something that is available if you want it.