I totally empathize with you. I too, am an only child, and have very overprotective parents. My dad has used the term "titanium umbilical cord" in reference to my mom...he has also said weird things like that about her, about locking herself in a closet and never coming out, etc.

Unfortunately I did not deal with that well at all, and I never said anything, and still haven't to this day. Definitely not suggesting that is or is not the correct route, but I can tell you my parents are well-schooled/sensible too so I can understand the confusion and the pressure.

I kinda ended up doing what you are. Playing by my rules and trying to avoid dad as much as I can unless I absolutely have to talk to him...yeah, still doing it at 31 and I don't even live with them anymore.

Just know that I am thinking of you, and I really hope it gets better, because I know it is hard, and totally stinks. (understatement, I am good at those)