Sleep and thought management

I’ve known for years how much more challenging it is for me to be in a good frame of mind when I’m physically exhausted (when I used to work the night shift I would find myself crying about NOTHING, and when I switched to days I felt like an enormous fog had been lifted). Occasionally I still get poor sleep due to my on-call schedule which is fine for now, but I’m worried as my husband and I are ready to have a family, and I know that will come with endless sleepless nights. I won’t be able to change my circumstance (the baby will need me whether I’m tired or not), so I need a long-term plan with managing my mind during physical exhaustion in order to keep myself and my relationships healthy. Do you have any suggestions on where to start? Reminding myself during my zombie/hazy/grouchy moments that I’m actually doing the thing I want to be doing sounds like a great idea, but it’s easier said than done. Thanks for any tips!