Op
It sounds an exhausting cycle:
*You moan / go to him for help
*He CAN'T give you what you need, but is a
'fixer' and relates everything to his field of knowledge
- you get angry for his lack of care
- he gets irritated
You may not believe in therapy, but it may be useful to read about Transactional Analysis.
In the nicest way ( honestly!) you have unreasonable expectations of your father. It sounds like he is overbearing and a know it all, but that is who he is.
On one hand, you are expecting him to be god like and all knowing, and you also expect him to be gentle and loving, and you are angry when he gets it wrong.
As a woman who is 40, you shouldn't be so worried about pleasing your dad. The fact that you still find it so important suggests that you DO have issues that need to be worked out.
You are a mum now OP. When we carry heavy burdens from childhood, it sometimes affects the way we parent.
Time to put some of those previous issues down, and leave them behind. Its worrying that you were so intent on ' pleasing him' that you ignored common sense, and widely known medical guidance. That sort of indicates that you are putting your childhood issues above being a responsible parent to your own child.