From what you've described, there does seem to be a ventillation issue at hand. Perhaps a vent tube or valve is clogged/stuck. Look at your gas cap and gas fill/vent tubes and see if anything looks awry. There will be a fill tube and a vent tube going from the fuel tank. See if you can compare your cap with a similar make/model/year gas cap. If you can't find anything visibly wrong, or if you do and attempt to fix it, let us know how it turns out.
Keep in mind: GASOLINE IS HIGHLY FLAMMABLE! KEEP OPEN FLAME AND SPARKS AWAY! We'd like to see you back here posting
Either way, check that gas cap and gas fill/vent tubes and call us in the morning. Welcome to Jeepz!