I think a pillow would make me a little nervous. But I know that DS2 was never going to sleep on his back, so I ignored the recommendations and put him on his tummy. I think you have to be a bit practical about things. If back sleeping isn't going to work, and something else does, then you gotta do what you gotta do. Personally I think an exhausted mum driving her baby around is a risk too, so you need to put things in perspective and do what works for you. I found that using a baby alarm with movement sensor helped me to have some peace of mind with Tom on his tum, so maybe that would help you too? Best of luck hun.