My wife and I are co-workers now, not a couple. How do we find our way back?

Since the twins came we have divided everything perfectly. She does days, I do nights. Handover happens at 7 pm and 8 am like a shift change. We are efficient. We are exhausted. We have not had a conversation about anything other than the children in months. Last week she said "I miss you" while we were both standing in the kitchen, and it hit me that we live in the same house and she was right. Couples who have come through the small-children years, how did you find your way back to each other? Did you have to wait for it to pass, or did something specific help while you were in it?