I think the experimental evidence for religion making people happier is horribly flawed (i might be a bit biased given i worked in a lab who was doing work on the subject). Here are some reasons:

Generally the researchers in the field assume that you can just do a linear analysis of religiosity and happiness, meaning using a scale of not religious to very religious and then making not religious=atheist, which is clearly not a good assumption. In fact studies have shown in the past a curvilinear relationship where the "more certain" positions of atheist and theist are as happy as each other . Also, even making sure that the people in the atheist pool are atheists is hard. If i remember correctly the pew research that showed a certain number of atheists in the country also found 40% of those atheists believed in god.

Second reason is : generally the studies use church attendance as its operational definition of religion which does not control for the social support that being in a church provides and when studies control for that generally they find no difference.

Now if this post is about if its true that it makes people happier what does that mean then please ignore.

Edit: i hope thats better