You can try to make the best of it. That's all you can do, so you do it, but it feels hollow and empty. It makes you depressed. It makes you want to leave.
The evenings are the hardest. There is no boss to appease. There is no structure. The evenings and the weekends make you feel lost and scared. Alone. You grit your teeth, and wait for the time to pass. Wait for the alarm that tells you it is time to be productive.
There is nothing worse than being unproductive. It is the cardinal sin which no one wants to face. No one even talks about being unproductive, even if they clearly accomplish nothing. Appearances are important. Never forget that.
If you do a good enough job of being productive in your work hours and invisible in your free-time, there can be a kind of freedom, but it is fleeting. Still, it is the closest you will ever get.
Enjoy it.