Rant/question

I am 15 going to be 16 in April. My boyfriend is 16 and will be 17 in May. My parents have granted us permission to date.. well at least he boyfriend and girlfriend (we aren’t allowed out of the house without parent supervision).. anyways they make comments about sex and how I am going to give in all the time. I have tried telling them that I am waiting until marriage and that sex scares me. But yet they still make comments making it sound like my boyfriend is all about sex. I have told my boyfriend my wishes and he respects me. My parents think they know how every guy works and think as well as how every girl thinks and works... so what should I do about my parents?