Welcome to the club buddy!
If your zip-less wetsuit is of the right size for you - your chances of getting out of it with no help from somebody else are ZERO!!!
I figured it out the hard way - was home alone when the suit got delivered and I really couldn't resist trying it...
On the bright side though, these are actually warmer than the zipped ones. Only wetsuits that do compare are much more expensive with a membrane behind the zipper like the Psycho Freak.