World falling apart

Its it normal to feel like your world is slowly falling apart and no matter what you do to try and keep your family together its just not working?! The baby daddy hasn't been much help nor has it gone smoothly sense I've gotten pregnant! Drink do drugs its just not like him will he be whipped back into shape and start thinking with the right mind set once he holds his baby girl. Or am I going to have to be a single mom that's divorced by age 20. Has anybody else had some things like this happen where your husband or boyfriend or whoever has just gone crazy when you were pregnant and once the baby was born just straighten up? Please comment cause honestly I just need some type of hope right now more than anyone know!