I've been a dancer for many years, first with West Coast Swing, which I continue to love to this day, and now with international ballroom. But I remember well how it felt to be a newcomer in a room full of social dancers that I thought were "experts." I was terrified to get on the floor with them.
It helped me a lot when I realized that people were only watching the good dancers, not the bad dancers like me. And second, after I became a good dancer myself (not great, perhaps, but good), I began to realize that most of the people I had considered "experts" were really only a figure or two and a couple lessons ahead of me.
My final realization, however, was the most important, and that was this: dancing is supposed to be fun, but it's NOT supposed to be easy. And it simply is not. It is hard to learn because it IS hard to learn -- or at least it is if you want to progress beyond a very basic level. You learn incrementally, and over time, you improve. That's the way it works for everyone, no exceptions -- even those guys on the youtube videos that we all watch.
Competition dancing is a whole different animal. But If you have a good instructor and you can find the time to practice once or twice a week, you'll be much better than 90% of the people on a social dance floor in just a year or two.
And you can take that to the bank.