Every 45 min or so, I take a 5-ish minute break. I usually use it for light exercise, but sometimes I have a bassline stuck in my head, so I pick up my bass and play it for a few minutes. Taking small breaks is good for you, and doesn't really hinder your productivity (source). Sounds like a win-win if you fit in your guitar practice.
by evening my hands are tired and i just want to zone out
This sounds like you could really benefit from taking at least some breaks, and paying attention to your workspace ergonomics. It should not be normalized that you are so tired after work, that you can't do your own things.
Now this is the solution to your problem, OP!