Good luck and dont think all men are the same, there are some real diamonds out there..
Agree ... :)
Also, heed what your instincts tell you. Take some time off and be on your own for awhile. Thoughts and opinions of our friends here really open up our minds in decision-making, but at the end of the day... it's gonna be you and your heart and your brain that make all the reflections and decisions... take time to recollect the happenings and encounters you had together before, and until the engagement... as well as to-date.
True enough, that once trust is broken, it's really hard to patch up and carry on with good faith... but... we are just people... bound to make mistakes...
Though it gave you this opportunity to see that side of him, reading his emails is probably not very advisable to do... Regardless, if you are willing to go through life as being married to someone, both parties have to trust each other... respect each other's privacy, as well as, no cheating :)
I hope you'll find the best move for yourself... no hurry as decisions like this one can be taxing... take your time.
Be it moving on without him, or, trying to patch things up... either way, whatever makes you happy....
After all, life is too short to wish you've lived it differently. Take care!