Sleepover with boyfriend

Okay so I really wanna have a sleepover with my boyfriend, but my parents have told me before they would never allow it. They say it's inappropriate for us to even be in mine or his bedroom. it's not even about having sex with him I just wanna fall asleep in the arms of who I love although I wouldn't mind having sex with him but my point is it's not about the sex I just wanna cuddle all thru the night with the person I love and I just really wish my parents put enough trust in me to do that. Any help? How do I approach this conversation with my mom? How can I get her to see my view on this and how do I get her to agree?