Books on how to be happy

It was not until a good friend had pointed out to me that I like being “sad” that I kinda started thinking the same. This might sound depressing, but I feel like all my life, I just convince myself that I am happy with whatever I am and what I do. I need to break the cycle of being delusional and accept hard facts and work on having a better quality of life. Please provide suggestions. I prefer fiction but open to non-fiction