Dont know where to write this

I'm one month pp since my son buth in February I have been the only to care for him my mother helps during the weekends and something during the week she works 10a-8:30p. My son's father who lives with us doesn't help what so ever. I do understand he does work (same shift as my mother) but at times when he see that I am tired or frustrated he does nothing. He doesn't take our son so i could rest a bit he doesnt like feeding him he doesn't do much. He rather be on his phone or playing games. While i care for our son 24/7. At night when I'm most tired he still does absolutely nothing to help me unless I tell him to watch the baby while I go prepare milk I'm so tired of it to a point where i kinda want him out.