I imagine there are spells to make them step back a little, but consider this: I highly doubt they're doing whatever they're doing specifically to bother you. I find that in most cases, parents do what they do in your best interest, because they love you. Be thankful for that love, and everything they've ever done for you. Believe it or not, they've probably sacrificed a lot for you.
Do you have a spell I could use? I'm pretty desperate. I don't think they love me, they never say it and you don't do this to someone you love! Especially when I am 28 and an adult. The only reason I live at home is because I am disabled.