A question often comes to my mind. There are times when it seems, to me, that to at least some extent, "truth" may be in conflict with "happiness". It seems like I have to choose between what is comfortable, easy, happy, familiar, or fun, and what is true, or what I believe to be true.
Those are hard decisions, no matter which way you look at it. Maybe you believe the church and the doctrines of the gospel to be "true" but want to pursue a romantic and sexual partnership with a member of the same sex, believing that will make you "happy". Maybe you are afraid to alienate yourself from your family and think you'll be socially "unhappy" without the church, but you believe that "truth" indicates the church is not what it says it is. Either way, you confront an apparent choice: truth or happiness?
Now, that's not to say your perceptions are always accurate, and most often I think you'll find things are not quite as dichotomous as you originally thought. So you may not actually be making as stark a choice as you first expect.
And in my opinion, truth must necessarily lead to happiness in the sense that you can only be happy with yourself as long as you respect yourself and believe you are living in some consistency with what you believe to be true. That kind of happiness isn't a bubbly, "hunky dory" view of life. It's being at peace with yourself and having some confidence that you are living with integrity, even if you must accept some things you hadn't thought you previously would or must let go of some idealistic perspectives you once held close for your own comfort.
Then there's the gospel/doctrinal perspective: if the gospel is, indeed, the "truth", then if you live the truth, life may or may not be "happy" the exact way you figured it should be, but in the end, this is a blip in your existence, and the eternal consequences will outshine what you have sacrificed in this life, probably more than you can possibly comprehend now.
From an LDS perspective: do you stay in the church because you believe it to be true, or because it has brought you happiness? Is one reason better than the other? Did you leave the church because you didn't believe the doctrines or because you were unhappy among "the saints"? Is one reason better than the other?
Or in life in general: do you treat people with kindness because it's just the right thing to do, a 'true' principle? Or do you do it only when it makes your world easier to live in? Do you choose to believe an urban myth, like faith-promoting stories, because there's no harm in believing something fabricated as long as it makes life a little brighter? Or do you prefer to know the truth about life, even at the expense of heart-warming myths, so you can face life with eyes wide open?
In my estimation, the question remains, as far as your motives are concerned: which do you choose? Truth or happiness?