Have you ever watched that show on MTV, "Parental Control?" In the show, the parents of a guy or girl do not like their significant other. So they set them up on blind dates with two other people. At the end, the son or daughter has to choose which person they want to stay with. Regardless, it’s his or her choice whether or not they stay with someone.
If someone’s parents don’t like you, then you should try to figure out what it is that they don’t like. If you find out it’s something about you that you absolutely cherish and that makes you who you are, then of course you shouldn’t change. But if it’s something you’re doing wrong, like cheating on their son or daughter, or always being abusive, then yeah, you should change. I wouldn’t like my son’s girlfriend if she was a jerk either. If you’re not doing anything wrong, then there’s really nothing you can do about it. It’s up to your boyfriend/girlfriend to decide whether his or her parents’ opinions really matter.
If your parents don’t like your significant other, then ask them why. Most parents just don’t think anyone is good enough for their kid. In this scenario, you have to either choose one or the other, or you have to try and make your parents like this person. I know that when I first date a guy, my parents don’t usually like him. In fact, the first time my stepdad met my current boyfriend, he told him that he would staple his you-know-what to a stump if he ever hurt me. But after a while, they got to know him, and now they really like each other. The point is it can take time for parents to warm up to somebody. Sometimes it’s as simple as your parents needing to know that your significant other really cares about you.