Why do some people look upon educated people and think there better then everyone else?

My mother in law and my sister in law both think I'm trying to be better then everyone because I'm college educated example: I have two degrees and starting to go back for my master's in January for Forensic Psychology. They think the way I carry myself and the way I am everyday is a bit much. I'm an introvert I'm quiet and shy and for example according to them: I need to be more assertive one of my flaws. Just because I'm quiet and not loud and didn't have kids at a young age makes me stuck up? I just don't understand there pyschology. I'm 25 my boyfriend is 35. I've been with the same guy for 4 years we have a pretty great relationship. We are the only ones in the family that don't have children yet. How can I blend in more so or become more assertive? 😂😂