i agree with the above two comments. i think john's showing his love in a form of life progression. he's saying that he'll love yoko from when he's lost and scared like a child ("in the middle of the night") to when he's growing up ("in the middle of a bath" - i see john as the dirty, splashing child and yoko as the adoring, loving mother cleaning and taking care of him) to when he becomes a man (in the middle of a shave) to when he becomes elderly and all he and yoko have left is their love and memories ("in the middle of a dream") to when he's dead ("in the middle of a cloud" - which sheensha correctly identified as heaven) it's a true shame that john and yoko never got the dream stage.
i agree with the above two comments. i think john's showing his love in a form of life progression. he's saying that he'll love yoko from when he's lost and scared like a child ("in the middle of the night") to when he's growing up ("in the middle of a bath" - i see john as the dirty, splashing child and yoko as the adoring, loving mother cleaning and taking care of him) to when he becomes a man (in the middle of a shave) to when he becomes elderly and all he and yoko have left is their love and memories ("in the middle of a dream") to when he's dead ("in the middle of a cloud" - which sheensha correctly identified as heaven) it's a true shame that john and yoko never got the dream stage.