I completely understand how you feel-it is totally valid to feel shafted. but unfortunately there's nothing you can do about it without making yourself look like an a**. i think you have to just be the bigger person now- maybe don't talk to his mom anymore? if it's driving you so crazy. you have to move on and live your own life. If his new relationship is built on lies he knows it and lives with it every day. you worry about you.