I was raised to be afraid of my bosses. They held my financial fate in their hands, after all. If I pissed them off, they would tell every hiring manager in the world I was a bad employee and I would never get a job. I knew I was to be grateful for $9.25/hr because it was so much more than minimum wage. I should never speak badly about my employers and days off we're for emergencies only. When you have a job, you give up the other things to make sure you can work.
Even as an adult, I have struggled to move past this. My last boss left me crying on multiple occasions, terrified I would lose my job and be blacklisted in my field. I was illegally disciplined by this boss for telling one of my coworkers not to contact me on my personal phone or when I was off the clock. I eventually quit that job.
Most recently, I have been proud of my growth. I no longer ask if I can take a day off for medical appointments; rather, I tell my current supervisor that I will need to leave early to make a medical appointment. I have firmly set the boundary that I will not answer any work correspondence off the clock. I get along great with my co workers.
Things still aren't perfect. After all, I'm an unpaid social work intern working part time for squat. But I feel like things are so much better for me now that I've left my abusive employer and learned to be assertive in a professional environment. I feel good.