Interesting story about your username as I always found it odd, like you know it's not random but it's not an acronym either.
Using a phrase to generate a password is a very good idea, I use that as well, and normally change a to @ or 1 to ! so I meet the special character requirement. The other thing I do is to use old addresses as that always has numerics and enough words where I can pick the first letter of each to meet the length requirement
It's not surprising that people find DLM odd. If I were in my senses, I might have chosen an easier to remember name. However, as a kid, I named myself whatever I wanted, and it became my internet identity. I even made a basic site with https://dlmmqb.com/ which I never updated.
People suggested that I shouldn't name my site dlmmqb, but for now, it will stay with me. The more difficult it is, the harder it is to forget once you remember it.
I'm glad to know that you also use it. Speaking of addresses, hmm, I wish you could observe how complex addresses are in Pakistan. Even my current location has many standards for addresses, and delivery boys often get confused. If I were to use addresses, I would also likely forget whether Block X was first or Flat ABC123 was first.