Controlling parents

Kat
So my boyfriend and I have been together for a year and a half. His parents have always been kinda judgemental of me and EXTREMELY protective of their son. I'll ask him to go on a stay-cation to a hotel a few towns away just for some privacy and he won't be able to go because his parents won't "let" him... He's 20. I feel bad for being frustrated since I respect his parents but does anyone have any tips on dealing with this situation or even the frustration I feel? Or am I just crazy?