Newby-how do people manage other family members?


I'm new to this forum and have so many questions.  My son is 10 and despite me raising concerns with various people for years it is only recently it has been suggested he may have ASD.  I don't mind that, it isn't great but he's been my son for a long time and a title won't change that, I was just hoping (naively) that people may get on board with supporting us a bit.

My son has managed to develop a whole range of coping strategies for himself when not at home (mainly just keeping a lid on how he's feeling until he gets home) but this has led to him being bullied at school, told he's irritating and ultimately not trusting people to help him because of the way they have dealt with him in the past.  So, his school are being better now but are frantically trying to gather evidence as they have ignored this for a long time.  The GP was useless so our referral was turned down, we can't get the school nursing service to answer us and the school are sending their SENCO on heaps of courses because they basically haven't got a clue (I'm glad they are trying though, it's better than nothing).  

Anyway, my husband is being as good as he can be although he's rapidly trying to get to grips with our situation but my family are being useless.  I took my mum to a therapy session with me that was recommended by CAMHS and she sat there saying my son has nothing wrong with him, he's just manipulative (she even thinks his toileting issues are part of him being manipulative).  This weekend she took him to London with his cousins and he coped ok when he was with them but one of them told him he was irritating and called him an idiot.  Rather than tell her that this is not how to treat people my mum and step dad let her get away with it and told my son to ignore her.  Well, my son now feels the people he should be able to trust can't be trusted and he feels let down.  This led to moodiness yesterday culminating in an absolute breakdown, his homework not getting done and him being in no fit state to go to school today.  I'm just at the end of my tether with trying to cope with it all and my family who just make it worse because they are so arrogant they think i'm wrong and they are right.