Wow, that kind of salutation in a Medium response seems kind of odd, doesn’t it?
I wouldn’t be so hard on yourself. Different settings and situations call for different types of interaction and language. Obviously, a toast will call for a different structure than if you’re just talking to a roommate throughout the night. You don’t have to introduce yourself or say “hello” every time you have something to say to a roommate, for instance.
It’s not a bad thing to want to get outside your comfort zone, but know that it’s also natural for language and norms to evolve. I thought this TED Talks video did a good job of showing how that can be beneficial: