I don't like the idea of "deserving " to be happy. What is, is. There is no use in fighting reality. Good things happen for no understandable reason and bad things do too. What I believe in is my power as the agent of my own life..if I do not like the way things are, if reality as it stands is not happy for me, I will work to change it. I am not big on allowed either. Who is allowing me to feel anything???
But i am a Buddhist. And I think my definition of happiness may be different from many. What I seek isn't even technically happiness but peace and connection to all living things. In my view, suffering is both inevitable AND useful. Nothing shines a light on your flaws quite like suffering. Most people can act like a benevelont monk when their bellies and pockets are full, they are warm and dry and well rested and feel welcome. When you are hungry, or lonely or cold or whatever, that is when you can face the places where you require growth.....