Im 16 PO and still cant get comfy on my side! Im not completely flat either.
Im still using my v pillow but i have a neat lil trick. Ive turned it sideways so the one side lays across a pillow and my head rests on it then the otherside of the v comes down my side so I lean against it. This was im not quite sleeping on my back and im not fully on my side, im inbetween the both and its nice and comfy so far! x