Needing to prop up boob during side lying

Hi guys so basically my boobs are really not suited for sidelying breastfeeding, they pancake out and nipples are right against the bed. I have to hold my boob up and the minute I let go my 3 month old loses the latch. I was told to use a pillow or something to prop my boob up but then surely that means I can't co sleep because it's a suffocation risk? Baby is so boob dependent right now because he's sick and I just want to sleep