Luckily the book is not the show and Stannis strategic goal is to get more support by supporting others. Plus Winterfell is burned down anyway, it is not a good strategic position to begin with. It's a symbol.
And then there is White Harbor, the Reeds, the Riverlands and Lady Stoneheart. Overall, the Northerners sending more support south to protect the Riverlands, was exactly the plan before the mess.
Book is book and show is show. And show memes like a divided north or stubborn Northerners (while nobody else has the problems) are not an issue. Everybody has a divided situation. Stannis is the symbol of a divided situation. And as always, he has to win people over to support him.