As an Engineering Manager, how do you handle internal stress?

I'm an engineering manager in my mid 20s and the stress is killing me. I constantly feel like I suck at my job and should do better, even though I've been meeting expectations. The manager I report to doesn't really provide me personal guidance, only if team or company goals are involved. But at this point the only solution I can see is to quit. My mental health has started regressing and I've worked really hard to get out of depression before.

Has anyone gone through this before? If so, how did you learn handling internal stress and self-imposed expectations?