Just some random advice that has helped me. I don’t work as many hours but maybe this could help you:

• My wife and I give each other 2 hours breaks on the weekend or “slow” days if they happen. This makes an insane difference. Having that time feels like a mini vacation. Even smaller breaks can help a ton.
• Simple dinners (30min max to prep and cook) help a lot. Meal prep if you have time or buy meals that you just need to pop in the oven. Not awesome but better than spending a ton of time in the kitchen.
• Make at least one plan for yourself a week. Something like meeting a friend for lunch can help me to look forward to something.
• Having either my wife or myself look after the baby helps ensure the other person can get some work or cleaning done. When we both are with the baby all the time it will mean more work later.
• Some days just suck but it’s not always going to be that way.