Just wanted to tell you how sorry I am that he's treating you this way and trying to put this on you like it's your fault. It's not your fault.
What I would suggest to you is to find Domestic Relations telephone number or office in your area and get your ass down there ASAP and put a child support order on him faster than he could ever give his ring back to you BECAUSE!!!!! Those kids are going to need it! I don't know how your state runs but PA will also let someone start a spousal support case with the child support. If your state is the same way, TACK HIS ASS DOWN! He is/was the soul provider and he's going to have to continue that for some time.
If he wants to be a jerk n ruin his credit and walk away from his financial obligations on the mortgage and every other bill, let him walk BUT he can never walk out on his financial obligation to his children because once you file a support order, if he doesn't work, I am sure your state has a comfy 6x9 cell for a DEAD BEAT MOM/DAD! PA gives the parent ordered to pay support 3 months before they come pick your ass up n haul it off to jail. They also take your license, hunting n fishing license and any extra curricular activities that require a license. You don't PAY... you don't PLAY!
And one more thing before I go and this is to anyone reading this... Don't ever let anyone tell you, I will provide for you. I have learned this years ago. ALWAYS, ALWAYS have a job, keep your skills up in a trade, have SOMETHING to fall back on. No one can take those skills off of you if they decide to up and leave or God forbid, pass away.
If you can, and you're willing, I would look into elder care. Personal care homes are a start. Everyone ages and nurses and attendants are in high demand like ALWAYS. If you can take care of a baby, toddler or child, you can take care of an elderly person. It's not entirely the same but it's the same when it comes to some things. I've seen people walk in off the streets looking for jobs and they have gone on to CNA's, LPN's and RN's. Get on the ladder and start climbing. If you don't want to do that, look into another profession. The thing is, start somewhere and TAKE OFF and don't let anyone ever tell you, you don't have to work!