Exclusive breast pumping

Hi it's a dad here and first time posting. My wife is solely expressing milk for our 3 week old baby. She refuses to go to the breast 90% of the time. She cries and screams and screams and throws her head back when trying. I was wondering if anyone has any tips on how to stop this so we can feed from the breast or if there are any mums who solely pumped and how did they manage with a timetable doing this, having a social life. My wife is really struggling with post natal and formula isn't an option as it will really make her mental health suffer. Any help or advice would be amazing and muchly appreciated