We should not be surprised that our job reflects life. Not every day of our lives are great days. Some are really bad. That's life.
What counts is that we have more good than bad days and are overall happy with where we are at. Same is true of the job. When it becomes a drain, it is time to move on. Nothing wrong with that. daays of doing the same thing for 30 or 40 years are over.
That said, we are responsible for us. No one else is. We need to keep us fresh and moving. When we stop doing that, we stop. period. Others can help, but in the end it is up to us.