Disclaimer: Naruto is not mine neither is the book by Harry H. Harrison on which this is based off of
Being a dad means getting mother and child home and realizing you're on your own
Sasuke had always told himself he didn't need anyone. From the moment when he saw his family massacred, he didn't need anyone. Until he got older and realized he needed to revive his clan. But still wasn't complete dependency on another human being.
Of course this wasn't the truth. Even a quote on quote "lone wolf" needs social interaction to stay alive. Sasuke needed someone, everyone needs someone. He needed Naruto for more than just his clan revival, he needed Naruto to survive. He didn't need his children just so they could be new heads of the clan, he needed his children because they made him a better person.
So when he walked into the Uchiha compound for the first time as a father he saw that Naruto now had a new responsibility added on to being Hokage. Sasuke would be required to help out but it should never be more than that. For the first time since he was a small child, Sasuke was left on his own to do whatever he wanted with his life.
It was a much scarier thought than he wanted to admit.