How do you maintain energy for side projects while you work full-time?

I'm months into a side project. As I near it's completion, it feels farther away. I work 40+ hours a week as an engineer. It's getting grueling. Even the thought of sweeping the floors or doing dishes gives me anxiety, because it isn't coding. And, my best brain energy is used up at work. Trying to stay positive and push through this last little bit. But, the grind — the grind is real.