I feel so foolish, I am sorry![]()
You shouldn't be sorry about something like this. Narcs can fool almost anyone.
On the plus side, you did what had to be done, and you're free again. This is a good outcome.
And it's definitely a learning opportunity

Some advice for you: as a general rule, you should come to terms with your own problems before getting close to someone with issues. Relationship-wise this is not easy in the 21st century, but it's still a good heuristic.
"Come to terms" there doesn't mean "fully resolve". If you understand and can live with your failings without negatively affecting other people, you're already in better shape than most. If, in addition, you are self-sufficient, mentally and emotionally stable, and resilient, you're in better shape than almost everyone.
It's ok to get help along the way, or to maintain a good state. What matters is the result, and having, at worst, a neutral affect on other people.