TLDR; Happiness derived from external factors is fleeting and ultimately unfulfilling. Here's a path I've taken to "better happiness".
July of 2016 I was as heavy as I've ever been. I would sometimes hit 250lbs and for a guy who was always "a stick" in high school this was WAY heavier than I ever wanted to be.
October of 2016 I left my position at Insight to pursue a dream/passion of mine. At that time I knew I'd be out of work for a while since I really wanted to try my energy at this Utopia42 idea. The idea has come in fits and spurts with some limited successes (and many failures).
As part of an agreement I made with myself at the time - For whatever this amount of time I will be chasing my dreams, I will also meditate daily and exercise regularly. I wanted to get to a solid 200lbs, and to be in better shape both physically and mentally (Book of Joy & Joy on Demand). Part of this was the commitment to embrace the Stoic philosophy of subsisting on the scantest of fare.
I've experienced that the attainment of the goal has no lasting satisfaction. The happiness and joy that I thought I'd feel when I set out on my journey came and went like a breeze. And you know what, that's a good thing.
This demonstrates the impermanence of all things, the ever changing expanding and contracting, the very fact that "this too shall pass". The wonderful thing is that if you can view this impermanence with equanimity then you can truly be more free from the suffering that comes from grasping after the things you want but don't have, and the things you don't want but have anyways.
The happiness never was in the goal, the achievement, the attaining. The happiness is in the way I genuinely feel in my body and how I'm so much more active now, and can easily touch my toes! Do you know how much more fun I have playing with my 6 year old? Tons! That's where the true joy is. Having those moments that will mean something to you as you reflect back over your life.
This is the most important thing. Happiness and Joy are trainable skills. No different than learning how to play a musical instrument, practice these things and you will get better at the skills of Joy and Happiness. Practice these things enough and your neural pathways will actually change (for the better) and your brain will grow (neuroplasticity) as has been validated by F-MRI brain scans. These skills are available in books, videos and audio, usually for little or no cost.
Here's why more people don't do it. It's WORK. Training your "monkey mind" takes effort. Similar to exercise, if you want "a 6-pack" abdominal, it takes an amount of effort and consistency. If you want to start seeing material benefits from mind-training (meditation) then in as little as 50 hours of focused, training you will start noticing these "meditative sweets" that give you the experience of what it can do for you.
If you'd like more Joy and Happiness in you life I can't recommend this path enough. I urge you to take the time to become curious about the vast landscape of your own mind and start spending time delving into your own journey in pursuit of more Joy and Happiness in your life. All the links to get started are right here. Simply take the plunge, I know you won't be disappointed.