Ok background. One of my dc has SN, he has ASD and various other conditons but the ASD is the important one for this situation.
Ex wants to take the dc away on holiday with his parents. However his parents have proven repeatedly that they don't take ds's ASD seriously, the last couple of times he has been with them alone, he has melted down because they drag him about from pillar to post, not with any bad intention I don't think but just because they don't understand that he struggles with change and being out of routine. When he meltsdown they just think he is being "naughty" and respond accordingly. This has happened a couple of times now. Ex cannot be relied upon because he drinks a lot and when he gets with his Dad the two of the just drink till they drop and his Mum gets all stressed out about it and does not put the dc first. I have seen this happen many times. There is a huge culture of drinking in their family.
He has told me he wants to take kids away at the end of the month, here in the UK, I told him I didn't feel comfortable with it for the above reasons and he told me I could go to to look after dc. I don't want to. We are separated and the last time I tried this both he and his father were abusive towards me, shouted at me, refused to seek medical attention for me when I was injured (was in the Middle East) and clueless about how to get it for myself. His parents live there but are back for a month atm.
I told him all this, he told me I was "psychotic", "need to see a doctor because of your mental health issues" blah blah blah, so I refused to engage with him any further. He stormed out.
So AIBU. He says I agreed to it previously, I didn't I just didn't say no because I hoped it would blow over as a lot of his plans do.
Sorry for the length.