My son's dad outted him

My son lives with his father. He was with me this summer and he dad ended up finding love notes between him and a boy at his Catholic school. Now this school is beyond homophobic. Last gay student they had there several parents petitioned to get him kicked out, he was bullied and harassed and shunned by the school until he left on his own. Turns out my son and this boy have been together a year and are having sex. His father is pissed. He's been back home over a month and his dad decided to OUT HIM to punish him. My son has been calling me crying. He's 17 and this is his senior year and students and adults are putting his life through HELL. His boyfriends parents already pulled him from the school but he still sees him. I wish I could get custody but I lost custody because I went to prison was n drug charges so the court is on my ex's side.