How do I keep my career in its place as just one part of my life?

You have done the hard reckoning already: the career is one room in the house, not the whole house. Many people never reach that. But holding it is not a one-time decision. The world will keep trying to promote your career back to the center, and you will have to keep putting it back in its place. The pressure will not come as a dramatic choice. It comes as one more late night, one more yes, one more thing that seemed small. Each is reasonable on its own. Together they are how the career quietly takes back the whole house. So the work is noticing the small ones. Keep a simple test. Before you say yes to more work, ask what it costs the rest of your life, and whether you would make that trade out loud. If you would, do it freely. If you would not, you just caught it in time. That small pause is how you keep the choice yours.