nik, My heart goes out to you and your son. I know you are in disbelief and pain but try to focus on something else, anything.
If I can make a suggestion, I know it is hard but you should try not to have any contact at all with him even texting. Send him the bills with a post-it note on each one stating "yours now", go ahead and make up some big envelopes that are already stamped and ready to go. As the mail comes in pop it in the envelope and DONE you don't think about it anymore. Only pay the essentials that you have to pay, power, water, gas, rent/mortgage, that's it...if it has his name on it, its his.
It is okay to be angry, bitter, and hurt and you NEED to experience those emotions, they are yours and you are right to FEEL them. Try not to become your emotions by letting your emotions dictate your actions or words. We tend to regret what we do or say later no matter how "right" you are. Try to release that negative energy elsewhere, exercise, punch a pillow, go out in the car turn on the radio and scream....get it out however you can but probably want to stay away from him and have no contact while you are EXPERIENCING your emotions.
You will get through this and it will get better and you are right, it will take time.
Formerly "missherlove"
Me49 XW49 M17 T19 S16 D20
Expose yourself to your deepest fear; after that, fear has no power, and the fear of freedom shrinks and vanishes. You are free.