Hi everyone - would welcome some thoughts or advice on a situation as I'm struggling to know what to do for the best.
Divorced, 2 DS (16/11) - 16 DS old fell out with his father 6 weeks ago - DS chose not see him for a few contact visits then plucked up courage to face his controlling father who promptly ignored him for the entire time. Following this, on my advice, he wrote his father a letter explaining why he didn't want to see him - his father has received this and has not replied for 3 weeks AT ALL - nothing, no text, call, letter - NOTHING!
He continues to see younger DS and is putting in way more effort than usual with him - DS then shares the exciting things they have done!
DS doesn't appear to be too bothered (although I think deep down he will be) - what should I do, if anything, to try and get ex to act like an adult and contact my DS - for my DS's sake (who is in GCSE year and could do without this) NOT ex! I find it heartbreaking that DS is being ignored like this 
Has anyone been in a similar situation?
Thanks.