A good designer is not only a designer
Working in software companies over the past 10 years I feel as though I am just now really being able to look back and state with confidence, this is what I learned, and hope that it can shed some light on your daily work/life balance. Ten years ago I started off as the only designer in the company I was working at and today have arrived to managing a multifaceted design team of 10 people. Working primarily for startup-ish software companies, my role has never been confined to solely a designer. Looking back I see my contribution more as an integration in a much larger machine, that works well with a strong balance between roles. So let's say that in order to be a strong product designer, you have to step outside of the design role. The foundation of my work is not making an experience look good - it is making it work for the user, taking into consideration factors such as business needs, technical limitations, system coherence, accessibility and market standards. Once these are settled and a balance of inevitable compromise has been made, trust me, it will look good.