In general, religious people seem to be happier than non-religious people - under various definitions of "religiosity," such as church attendance or professed spiritual beliefs.
Don't let perfect be the enemy of good.
The days are long, but the years are short.
Act the way you WANT to feel.
Be a storehouse of happy memories.
We need to have intimate, enduring bonds; we need to be able to confide; we need to feel that we belong; we need to be able to get support, and just as important for happiness, to give support. We need many kinds of relationships; for one thing, we need friends.