Shurm, You are not pathetic. You just seem to have gotten swept up in a whirlwind romance... with the wrong guy. Make no mistakes that this guy is the wrong guy I am sorry to say that since my gut tells me if he showed up at your door today you'd take him back... just to ease the pain of missing him. I could not blame you for that... many people will do anything to ease their suffering even at the cost of suffering greater later.
Its like starving to death and your stomach in terrible pain... there is a plate of food, your favorite dish there on the table and its warm and tasty... but its also poisoned. Eating it will be the worst thing for your health... but you are hungry.
I think that you should be happy for the time you spent that he made you smile, time wasn't wasted... you made the most of every day with him. But it was not to be. He is not anywhere near ready to settle down yet, as his actions clearly show.
Right now him not signing that paper is holding you in limbo. He probably is enjoying that control or he would have signed the papers allowing you to have closure and work towards healing...but right now are in a sticky situation.
Its hard going on with your life , maybe meeting an awesome guy and having to explain you are not technically single. You having more legal experience should know if there is something you can do to expidite this divorce. He has abandoned you. I believe thats good enough grounds aside from the cheating.
You sound like a good woman with a free spirit (or you never would have taken such a leap of faith to begin with) don't lose that part of you along with losing him. Life is short AND life is long, spend it with someone that makes it better... not worse.