I already have a lot of crap days and feel like I want to walk away sometimes so I'm petrified that this might be what breaks me.
Don't forget that you're in the last weeks of pregnancy, feeling tired and impatient at the best of times. It will get better after baby arrives and you get back on your feet again! Just give it a little time. There will be a few chaotic weeks of adjustment, and then it will be OK.