You are not alone! At 3 months of age my advice would be to listen for him to start stirring and go straight away and pat/rock him back to sleep. I found this did help my daughter to move peacefully from one sleep cycle to the next. Most importantly however, surround yourself with people who subscribe to the same parenting approach and avoid women who like to tell you that their children sleep like logs. This will only frustrate you. Hang in there. After all how many 17 year olds do u know that are still dependant on their mums for sleep?