Reversing Etiquette

Hi, New to caravanning this year and as of yet I've had the luxury of finding a pitch that I can easily reverse on to.  We're due to set off at the weekend on our summer vacation and I'm concerned that the sites will be a lot busier as the schools will have broken up.  I've seen some pitches that seem pretty much impossible to reverse onto and I'm concerned that I might just end up with one of them whilst we're away!  If you are faced with such a pitch and you dont own a mover how do you tackle the situation.  Is it acceptable to un hitch and push the van on?  I'm also concerned about that as my wife would struggle to assist me with this and I'm not convinced I could move a fully laden van on  my own.  Thanks