Statistical data analysis should not be attempted by amateurs. Maurice Vellacott, for example. The Fetus©™ fetishists insist on claiming that there is a cause & effect relationship between abortion and mental health for women who have terminated pregnancies, as well as between abortion & breast cancer.
Now we hear that 'Murrican states who have banned same-sex legal marriages seemingly have higher divorce rates, here. * Apparently those couples haven't heard the claims shrieeeked over and over again by conservative religious organizations such as Focus on the Family and R.E.A.L. (anti-feminist) women to the effect that heterosexual marriages are under attack!
Here's an excerpt from this pollster/poll compilator:
The differences are highly statistically significant. Nevertheless, they do not necessarily imply causation. The decision to ban same-sex marriage does not occur randomly throughout the states, but instead is strongly correlated with other factors, such as religiosity and political ideology, which we have made no attempt to account for. Nor do we know in which way the causal arrow might point. It could be that voters who have more marital problems of their own are more inclined to deny the right of marriage to same-sex couples. [...]
At the very least, I would be surprised if there were any statistical evidence that interpreting the right of marriage to apply to same-sex couples would be injurious to heterosexual couples in any material way.
*Don't forget to read the batshitcrazy comments by the usual US rightwingnuts, teabaggers, homophobes and religiously disordered zealots.