Hey I have PGP/SPD too!Good that the doctor was so thorough! Mine has eased off slightly since i have cut down my hours at work and my husband makes me rest more. I have a belt, which is ok, its not hugely usefull but some times it takes the edge off of it, i think rest is really the only solution (altough easier said than done)
At night i prop pillows everywhere in between my legs back and bump, although i sleep flat alot of the time and prop a pillow between my bum and legs for some reason that feels more comfy for me..
Think its finding best positions for yourself, and pelvic floor exersizes.,,
Hope it eases for you soon! xx