Would you say my parents are harsh?

My mum and dad are great! I can't live without them. Although I have one issue, they don't let me on sleepovers! I am epileptic and so i guess that could be a tiny reason but even so I only have fits like once a year. My friends constantly ask why I can't sleep over at their house but the truth is that I don't know why. I have asked hem why and sat them down and talked to them but that dos not work so please nobody suggest that. But do you think that my parents are harsh or too over protective? Oh im 13.