9-5 is miserable if it's all you do.
There are 24 hours in a day. You need to sleep seven. Let's budget 30 minutes commuting each way to work. And we should figure two hours for shower, meal prep, etc.
This leaves 6 hours each day to do whatever you want. For a young, single person -- this is fantastic. If you spend those six hours watching TV, yes, that leads to a miserable life. But you can go to museums, join a running group, try new restaurants... anything you want.
If you're miserable in your 9-5 job, find things outside your job that excite you. I think you'll be surprised as to how much it helps you enjoy everything - even a crappy job - just a little bit more.