This question is harder than it first seems. The love of parents and the love of a mate are different but equally wonderful things. Giving up one to have the other is never easy. Never. Still, sometimes you must choose.
When facing the truly hard choices in life, it can help to ask advice from those people you love. Usually the first choices would be a siblings, a mate, or your parents. In this case it sounds like that will be really hard but it needs to be done. In the end, if you cannot find a way to include both parents and boyfriend, you will have to lose one to have the other.
Last thought: You might give your parents several more tries to see your side of it and to help them understand how much this worries you. Being parents, they will most likely mess-up the first few chances.