So won’t let me have a break...

So I work fulltime. My SO lives with me and doesn’t work right now. We have a 7month old together. He or his family watches the baby while I’m at work. Soon as I get off, I go get our son from my SO because he is usually visiting his family which he goes over there everyday. If I’m not working, i have our son. I never complain. So today I asked if he could keep him a little while longer so i could go home and bathe and just take a break.... he literally started guilt tripping me saying things like “you are the reason he is so dependent on you” “you dont know how to sit him infront the tv to keep him quiet while you take a bath?” And “you don’t know your own child” all of that was basically because he feels like i shouldn’t have any free time without the baby. And i dont have any other help beside him and his family. I’m just a tired working mama...