@Thenose
sleeponeday
Yes, I have two disabled children, and one is non-verbal.
"children are often the cause of adult relationship problems because they place huge demands on a couple."
I completely disagree. Adult relationship problems often develop as a consequence of adults' unhelpful responses to demanding circumstances. Blaming a disabled child for an adult's failure to maintain a healthy adult relationship is unhelpful for everyone.
Nobody's blaming anyone in acknowledging a basic reality: that huge demands, such as those of small children, place additional strains on couples. It's a statement of situational fact, not a moral judgement.
It's really odd that you seem set on refusing to recognise that the colossal demands of parenting can strain marriages - and why are you so set on the idea that honesty must equal attribution of blame? It's not anyone's fault; parents or child. Less time to focus on one another, less energy of all kinds, less money, less sleep. What sort of robot wouldn't find that placed a strain on a relationship, however wanted, loved and fabulous the child is (well, mine are!)? And there is neither blame nor shame in that, nor in acknowledging the truth of it for most - or shouldn't be.
I think acknowledging it helps people, speaking as someone who has been married, mostly very happily, through two decades. The very early years are hard for most of us, in relationship terms. The early years are hard for lots of fantastic mothers I know in parenting terms, too - that's why charities to support them exist! If we weather times of stress and strain, and the marriage was good to begin with, you get past it, but that doesn't mean those rites of passage are easy, or that the strains don't occur. Why are you of the view that blame has to be apportioned - to anyone - by the acknowledgement of some extremely well-researched fact?
The OP has no right to more care than her mum is offering, which isn't that low. But she has every right to express distress and frustration with how hard this part of her life is for her, and to seek extra support, and to find that the struggle placed a lot of strain on her marriage - which is, from women I know in our shoes, not unusual, though in most cases thankfully it passes. All of this is okay. None of it is anyone's fault. So let people vent, and then try to work on a plan to make life easier and better for all of them - which, surely, supports the child you purport to be concerned for better than castigating their mum? No?