Very relatable. One thing that helps some people is treating the "second job" like any job: cut the tasks, not just push harder (I'm on a medical editorial team that writes about ADHD, so general ideas, take what fits):

• Pick 2-3 systems, drop the rest. A calendar with alarms, one capture inbox (notes app or paper) and a weekly 15-minute review cover most of it. Ten half-used apps are their own workload.
• Automate the boring part. Auto-pay bills, recurring reminders, pill organiser or a phone alarm for meds, groceries on repeat order. Every decision you never have to make again is attention saved.
• Make the environment do the work. Keys always in one bowl, a "launch pad" by the door, the gym bag already packed. Less remembering, more defaults.
• Protect sleep first. Short sleep makes every ADHD symptom worse the next day, so a fixed wind-down alarm often pays back more than another productivity trick.
• Body doubling and external accountability (a friend, a coworking call) can replace a lot of willpower.

And it is fair to be frustrated. It is real extra work that other people don't see.