My son is 15 and has lived with me his whole life. Me and his dad split when he was 2 and I remarried when he was 4. My other half is a serving military personnel and we have been posted 200 miles away. My ex wants my son to move in with him - he has not lived with him or stayed more than 3 days since he was 2. Because he says im being selfish making him move that far away. He already lives an hour away and he sees him as agreed every 3 weeks, I’ve said I will continue with arrangement wherever we live but my son has come home from his visit to dads in such a state. His father has started the mud slinging about me and my husband. I just don’t know what to do.