You're in emotional survival mode, caused by stress, too much information and overwhelm. Managing those emotions becomes your priority, leaving little energy left for taking action. It's a rut ADHD people fall into. And of course thee last thing you want to deal with, on top of all that, is going for an ADHD diagnosis.
While overwhelmed is an adjective, ADHD overwhelm is often used to refer to a symptom of attention-deficit/hyperactivity disorder. For adults with the disorder, it means feeling like your brain is flooded by excessive emotions, information or stimulants that are unable to be properly sorted or prioritized. ADHD overwhelm can essentially lead to you feeling frustrated and upset with yourself, causing you to shut down completely, both mentally and emotionally.
Adults with ADHD are more sensitive to feeling overwhelmed than neurotypical adults. For those with ADHD, there is a difference or disruption of neurotransmitters in the brain that are required to carry out Executive Functions needed to handle tasks. These affected transmitters are needed to stay focused on completing one specific task or initiating a plan of action.
Without the ability to carry out the required functions to handle a situation or task, an adult can experience ADHD overwhelm, causing them to feel stuck.
This site has some good information and strategies. It helps to understand why this is happening, so you're not blaming yourself.
https://www.beyondbooksmart.com/executive-functioning-strategies-blog/adhd-overwhelm-why-it-happens-how-to-control-it
I've dealt with it all my life, it's horrible. I was not diagnosed until my late 50's. Don't suffer needlessly, go for help if you can.