"If this or that were different, I would be fine!" Do you know that? That you think your happiness depends on something changing on the outside? A person or a situation?
How would it be if you were one hundred percent responsible for your own happiness? "Don't seek to change the world," says A Course in Miracles®, "but change the way you think about the world!" As you learn to look at the world differently, that changed perspective will also change what you see.
Wanting to change the outside world is like sitting in the cinema. There's a movie on there that you don't like. Angrily you run to the front and scratch the screen to change the film. But it just keeps running, undeterred by your effort. While you hurt yourself and your hands hurt. The only place where the film can be changed is in the projection room. From there you can pause the movie or load another movie.
What is the projection space in your life? Your own mind: your opinions and thought patterns, your beliefs. There you can change something. And then what you see changes too.
As I posted before: do you see the glass half full or the glass half empty? The power of decision is yours. Only this power is available to you. Use them wisely.