10 week old plays for 10 hours without napping breaks

I have a 10 week old baby boy and he has started a bad habbit of not sleeping which is worrying me. I mean he wakes up at noon and will not nap nor sleep at all until midnight at times. This has become a huge problem as l have OCD and l find that l cannot manage to do most things in the house as l do not want to neglect him also it is taking a toll on me as we pretty much breast feed and play in those hours. I find it exhausting that by the time my fiance gets home and l am trying to implement some sleep training that l read about he feels that l am neglecting the baby.