Custody and moving out of the state of oklahoma?

Ok... I am 27 with a 3yr old son and I'm in the middle of a custody battle and only because I want to move out of state. Now hear me out, my sons dad is in oklahoma drug court program. He's been arrested several times for non compliance for times ranging from 2days to 5weeks. I know he can't win ful custody of my child with that background but I fear he can keep me from leaving. I have lived in the same place with the same job for 3+yrs a 2bdrm with just my son and I. I work 50hrs a week to support us. His dad is ordered to pay 105/mo in child support and since 5/09 has paid 250... He currently lives at his moms where they share a 1bdrm apt. And my son sleeps on the couch. He has not held a job longer than 3mos in the last 4yrs. his dad is there, dont get me wrong, when im workin he watches him outside of daycare hours. We went to court to do a temp custody order and I told him I want to move to GA with our son he suddenly contested it all and demanded an attorney, so absolutely nothing happened. And what was previously a very civil friendly relationship, was now an all out war. I understand kinda. My new boyfriend and friend for 10+yrs is in the marines and recently got stationed in GA and asked my son and I to join him. Attorneys are expensive and I offered him alternating holidays, summers, sprng breaks, even to drop his childsupport. Where he would be going there would be soooo much opportunity for my son and I and all needs will always be met. My sons dad doesnt want "another man" raising our son and is being quite childish. My question is... how do I get him to see. 1. That he cannot win. 2. Its something that could be wonderful to my son. And also is there a way to bypass going to trial on this if he does not agree? I'm runnin outta time here.... any ideas thoughts or suggestions would help. Thank you.