This is true! From my experience those who are religious tend to be a bit happier than those who are not. From a purely rational perspective I wish I could be religious as it seems to be good for you in a general sense, unfortunately my brain just isn't wired that way. Can't make yourself believe.
From my own personal experiences, religion gave me a fair amount of comfort/peace of mind that could have translated into increased happiness. Knowing that you can rely on some greater standard and power relieves a lot of burden and uncertainty in figuring out how you should live your life. Belief in the afterlife relives fear of death and gives you all of these wonderful things to look forward to. There's just a basic attraction in the belief that the whole universe has some kind of grand direction and purpose.
But ultimately it was nothing more than a nice delusion, and if I had a chance to stop myself from going down that path I would have. It adversely affected a lot of decisions I've made and in some ways I think in the end did leave me feeling more hopeless. Many people are indoctrinated with religion at a very young age and finding out for themselves that it doesn't really fit with reality is jarring. You see a lot of accounts of atheists who hate religion because of how they were mistreated by religious people under religious ideals, or how they see other people have been mistreated. You don't see that many accounts of people who stopped believing in it even though they felt it had a strong positive function in their life.
It's not hard to see how all of this would correlate less religion with less happiness (and as everyone knows, liberals are on average less religious than conservatives). But like it's been said, you can't force yourself to believe. Once you realize Santa Claus isn't real you can't go back, no matter how happy that belief made you.
Atreus21 said:If you arrive at the conclusion that there is no ultimate meaning to life because the universe is fundamentally purposeless, then the only rational conclusion is to maximize happiness.
You don't manufacture happiness. And just because you don't believe that intelligent beings created the world or people doesn't mean that you lose interest in humanity or the world at large.