The worst of it is that Adult Social Care and other Charities and services were totally disinterested while I was in a relationship with him, as he was MEANT to support me and the DC's, as far as they were concerned. Regardless of whether he actually WAS while he was doing these split shifts.
In fact, he did nothing. NOTHING. He got in from work, did NO housework, NO childcare, NO cooking, stopped even picking his own clothes up and leaving mess behind him wherever he went.
The minute he walked out (He couldn't deal with my 'neediness' and 'nagging' any more...), all these outside Agencies have slowly started to become involved and helping me.
The straight fact of it is that the OP will get VERY little help from outside agencies while she is in a relationship with someone, as the way they see it is that there is a fit, able adult to support the OP, and they only have the funds to support those that DON'T have anyone fit and able to provide it.
I can't get over the fact that he is prioritising HIS happiness and well being over that of his DD's. I know only too well how important these activities are for a DC with Autism and physical difficulties. To take a job that means she will have to stop those activities, which could undo all the good work the OP has done so far, is verging on cruel, and IS selfish behaviour on the part of her 'D'H.
I have to say, it is less stressful being a Lone Parent supported by Charities than it was being part of a couple that was being left totally unsupported because the person who should have provided that support basically 'checked out'.
I feel for you, OP. You are in a no win situation - your 'D'H takes the job, your DD and you suffer, you feel resentful. Your 'D'H doesn't take the job, HE feels resentful.
Will he listen calmly and without being dismissive to your concerns about the effects on your DD, and how HE proposes to solve the transport issue? It should be HIS responsibility to arrange alternative transport to your DD's activities, as he made that commitment FIRST, before committing to this job. Your DD shpuldn't have to miss out because he is not honouring his pre-existing commitments to drive her to these activities, so what is HE going to do to ensure that that prior commitment to his DD's well being is honoured?
That's how I would approach it, with each of your issues - due to both your disabilities, AND those of your DD, he has pre-existing commitments to ensure that you have help every evening, and that your DD continues with her activities. As HE will no longer be able to personally honour those pre-existing commitments, how is HE going to ensure that those commitments are still met?
Is he going to make sure your DD has reliable lifts to her activities? Is he going to cook dinners and freeze them to take the strain off you? Is he going to do more around the house and prepare things so that you are able to spend the evening with your DD, who needs you? How is HE going to ensure his pre-existing commitments are met?