This is said with much love and I don't mean to sound harsh, but....
Why do you keep reading all these e-mails?? Stop letting others try and influence you. It is not his mom's place to be telling you he has changed. She is acting just as co-dependent as you are. The only person that can show he has made a change is him, and that can not happen over night. It will take time, a long time. These day to day e-mails are futile.