Separation / children

Asking for my best friend . She is married with a 2 year old son , and 29 weeks pregnant . Her husband is always miserable , mean , so nice to strangers and other women . She is no longer attracted to him - he dabbles in different drugs and smokes a lot of weed so he’s slow . She wants to leave him but wants him to leave their apartment so she can raise her little ones there . He always pokes at her for not working - even tho they agreed she would be a sahm. Should she stick it out ? She’s not happy anymore because of him . And stressed during pregnancy . She feels she can’t be happy and it’s toxic for friends and family .