I have seen a few girls say they still dont lie on their back year or so later! yet others do!
personally im only 16 days post op and i cant imagine ever lying on my side and it feeling normal never mind my front!! I hope as they start to feel more like my own boobs i will feel more confident to try it out as ive always been a side/front sleeper! you do get used to sleeping on your back though if you make it super comfy all around you, sorry I couldnt reassure you anymore but its definitley possible – eventually lol xxxx