My son keeps running away from his mom

Me and my ex wife divorced 4 months ago and my son keeps running away to me or trying to stay past his days with me. Right now I have every other weekend. Split custody is kind of impossible because of distance but he doesn't wanna live with his mom and we are in an intense custody battle. She has used the fact that I was in the military and have PTSD and childhood trauma as proof that I am not a capable father and couldn't take care of a 15 year old. She's also trying to discredit our son by throwing him in mental health hospitals by saying he was harming himself and every hospital has said he has not harmed himself and he gets released within a day because there's nothing wrong with him. So much so that she's had cps called on her by these hospitals. She's leaving that out when she's having her lawyer say that our son is mental ill and can't be trusted. But I do have the medical records from these hospitals and none of them have said anything is wrong with him and they found no evidence of self harm. I am trying to do this the right way but when he keeps running away to me and begging me to keep him it breaks my heart when I have to tell him he has to go back with his mom because I can get in trouble. I just want this custody battle to be over. We have court again tomorrow so pray for me.