Marriage isn't supposed to make you happy. It's supposed to make you married. Here's how it's supposed to work.
A large portion of our single lives is taken up with trying to find a mate. Once you find that mate, a large chunk of life is left free to explore life, develop hobbies, pursue interests. So then you go become a well-rounded person and become happy, content, satisfied. And he does the same. And at the end of the day you come home to someone who cares and asks how your day was. And then you are happy, content, and satisfied, and together. You are happy together. Not necessarily just because you are together, but side by side. But then people decided at some point that the other person in the marriage is supposed to shoulder the responsibility of keeping you happy, of making you happy apart from hobbies and outside interests. That the old model of Grandpa in his wood shop and Grandma in her sewing room, together until they die in their teak rocking chairs, was somehow bad. They were only companions, just roommates, and that wasn't enough. So now we all expect some sort of impossible fireworks from our marriages and when it doesn't happen we get upset. Perfectly functional, happy, content marriages are now unsatisfying because our spouses are ballsy enough to expect us to go forth in the world and make ourselves happy. Didn't they know that was their job?!