> Instead, I need to pick projects that I care about and not spend long stretches of time on things I don’t. I'm getting this feeling myself more and more lately. And I've only been doing this for a little over 5 years. Although, I wonder if I'll have this thought regardless of what field I am working in.
After similar lines of thought, my conclusion is that you have to embrace the process of writing code and not get too personally invested in the end product - it doesn't belong to you, and a company can and will sell it, scrap it, or let it decay slowly. Step back and be grateful for the opportunity to apply your skills to help someone else create something they felt they needed, and don't worry about what they do with it after the fact. I've found over and over that caring about a project too much leads to disappointment - the more bleeding edge the project, the more interesting it is, and the more likely it is to die. Embrace the idea that your job is to help someone with a short term goal. It can be fun, but don't let it be your life. Life is about people, not things, and certainly not the code you wrote last week. Help someone by using your skills and move on, it's very rewarding.