I really need a lot of advice. please help

So since I got pregnant my son and daughters father has completely shut down even more so than before.     He's never provided for my son and has never helped with anything.  He spends days without seeing him and then calls me from random numbers always wanting me to drop everything and let him see his son.    He makes plans during the day/week to see him or go bowling or something when I get off work and then constantly cancels to be with his friends.    He still loves to party and smoke weed and drink.  He's still in the mode of oh yeah Friday nights are the time to party! Weekend!   But he doesn't even work.  And hasn't help a steady job for more than three months at a time and years in between.   So basically he's a looser.    I've always given him the benefit of the doubt until now.     Now it's different for some reason because I'm having a baby girl.  From the moment we found out I was pregnant he has said he regrets it and hates that I'm pregnant and hates me and it's just terrible.     It's was definitely an oops one night stand with him.     So basically I'm 21 weeks pregnant now and he's almost never around.   So I put my foot down.    The last time he made plans to see his son he cancelled to go party with his friends first and then he will see us.  And this was on a school night.   I always tells him he's not allowed to come over if he's high or drunk because he acts like a complete idiot and eats all our food and tortures my son ( he thinks he's being funny).  It's terrible.   So this last time he cancels I tell him to jump off a cliff and I'm done.   He has chosen his family and his son for the last time. I thought for some odd reason since it's a girl this time he would completely change.  He's even worse then before.   So I told him I'm done and he isn't coming in and out of our sons life anymore and my baby needs a full time dad with consistency. He needs a dad who is involved and supports him!   He doesn't play catch or teach him anything!  When he does come see him he goes and crawls in the bed and watches tv.  That's his version of seeing his son.  So basically I said eff you and I'm done and don't even call ever again until you man up. Your not seeing our boy anymore until then.  So he tells me I'm a witch and he hopes I die giving birth and I'm all this stuff and I just blocked the random number.

It's been four days now and I'm atatting to feel super guilty.  It's almost Christmas! Like what do I do am I doing the wrong thing?!!  This man is a complete loser and I have to save my kids from being like him or thinking how he treats women and how he lets everyone take care of him is ok!   Idk I feel bad  I need advice.  I'm thinking of doing a natural birth and I have to have complete serenity and I can't if he's around. And he just told me he hopes I die.     I have to take that away from him to to teach him a lesson????   He's so childish...  please help me and give me advice.  Should I cut him off forever until he mAns up and changes. Should I seriously keep the birth of his daughter from him.   Idk what to do.