I'm wondering if this song is about being in love with someone, but it's a childish or unrealistic love. She doesn't want to grow up; growing up would mean discarding such feelings, and it's easier and more enchanting to emotionally stay where she is; "this place is so lovely / it kind of makes me very happy". "Make believe is much too fun", i.e. imagining that the relationship could happen is better than owning up to the fact that it probably can't.
I'm wondering if this song is about being in love with someone, but it's a childish or unrealistic love. She doesn't want to grow up; growing up would mean discarding such feelings, and it's easier and more enchanting to emotionally stay where she is; "this place is so lovely / it kind of makes me very happy". "Make believe is much too fun", i.e. imagining that the relationship could happen is better than owning up to the fact that it probably can't.