How can I ignore this and go on with my life?

Simply ignore it, because one day those people may not be remembered and they will have their own life they chose to be. If these people piss you off, just stay as their acquaintances and nothing more. It will only be for the time being, and yes - they will learn the right way, they just haven't realized what is the right way yet. Or maybe they wont realize it, that's really their decision. But don't be angered by them, don't worry about them, worry about yourself. That you will be a better person, that you will be caring, socially aware, and competent. Hope this helped. (: