Does Wendy Marvell have a couple? If not, why? Fairy Tail has ended, but I realize that Wendy doesn't seem to have a relationship with a man as a couple.

I think it's logical because she's too young to get a couple.

Is my reasoning true? Otherwise, is there any reason why she doesn't have a couple?
[Potential spoilers for the end of the Fairy Tail manga (chapter 545) below.]

Simply put, Wendy is not shown nor implied to be in a canon romantic relationship at the end of the series.

The reason is simply that the author chose not to officially pair Wendy with anyone. However, we as fans of the series are entirely free to headcanon as we like!