That sounds awful. I'm sorry your dealing with such head sensitivity. I tell my girlfriend to be careful when she hugs me. Luckily us men tend to go for the handshake instead of any bodily contact.

I am not suggesting this is the case, but maybe this is an anxiety issue? I know I've dealt with a lot of anxiety from minor bumps. I'm sure there are two sides to it with one being the bump and the other the resulting anxiety with both causing symptoms. If you can eliminate the anxiety about the hugs I'm sure you will be better prepared if a stray hug does come your way. This has at least been my latest approach as I think a lot of my issues stem from anxiety of further injury. It's a perfectly natural response but it has to be dealt with before it worsens and becomes a psychiatric problem like mine.

All the best,
Danny