Depression Support Group
Depression is a real and debilitating condition that is often misunderstood by family and friends. Its meaning can range from a prolonged period of sadness to an actual mental illness with specific symptoms. Find and share experiences with others who are going through the same struggles.

It can definitely come across as positive and like you're willing to learn from the situation when you ask what you can do to improve your performance to advance within the company and what could have been done better to get this particular promotion....just wait until you are calm to have this conversation with your supervisor.
I have an internal critique voice that goes over what I do and what happens.
I'd ask the question - what am I lacking, what were they looking for that I didn't have (or portray). Have an honest conversation with yourself and without emotion or anger and find what you need. Often in your situation, it is a matter of highlighting that crucial piece of experience. It takes a lot of honestly look at what we are lacking but it will serve you well. Find out what the difference is and do that. Hope this helps.
Also, remember, the best time to look for a new job is when you have one. You can afford to be more picky, take your time find a company that has a reputation for promoting from within or seek your dream job. Almost all companies allow you NOT to put a checkmark in "Okay to contact current employer?". Seems like, if you are a top producer there's companies looking for that and you have other options.
Often I have seen people give 2 weeks or 30 days notice to go to another job and boss decides to try to persuade them to stay. Sometimes they take the boss's offer/stay and sometimes they say there is not enough money in the world to make me continue to work for you.
I am am old retired lady now, I have been in similar situations as you are and I have been the boss in my past. I have almost always asked potential employees why they left their last job.
I would be out front with potential employers about the reasons I was unhappy in your current job. (Lack of upward mobility it sounds like in your case, for one.)
Here's to finding to job of your dreams
That is encouraging to hear.