@Songbird76 I'm going to give you a little background into my family because I think maybe it will give you some insight into yours...
When I was little, I was such a daddy's girl. My mom always tells the story about how we were staying at Coronado Springs, and she was checking in, and my dad took me into the gift shop, and in the ten minutes that it took her to check in, he and I came walking out, and I had a little 101 Dalmations purse in my hand. And my mom was like "Really? She's got you wrapped around her finger."
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And we were like that for the longest time. After my brother was born, as I got older, we used to go off and do things just the two of us. We'd go in the parks late at night and ride all the big stuff, he'd take me to Orioles games without my mom and brother, you name it, we did it.
And then came the autism diagnosis with my brother.
I was 11 when he was diagnosed, and at first, nothing really changed. But then, the pressure to keep my grades up started coming on a lot harder, and it came on stronger and stronger in high school. Then came the pressure to be a lawyer, like him, and for a while, I was all for it, until I wasn't. I decided I was too emotional for a legal career, and the business side of it would bore me to tears. He was not happy about it. I later found out from my mom that his expectation was that I would join his firm. That was never happening, even if I did become a lawyer. Then, when I was applying for colleges, he wanted me to go to his alma mater. Well, his alma mater was not like it was 35 years ago. It was huge, basically a school where anyone could go, and I was not impressed. It was my safety school, and I told him that. I ended up picking a small, private school that he was not a fan of, but in the end, it was a perfect choice for me and I got an excellent education there, and I got a business degree, which made him happy, and me because it was a good choice. Then came more pressure for law school, and I was more firm that it wasn't happening.
But then I realized that I somehow stopped being daddy's girl and had become the son who was carrying on the family responsibility. And I thought, "When did this happen?"
And that's when it hit me: all of this started after the autism diagnosis. When he got a son, he had expectations for him. That he would be like him, that he would go to college, maybe to law school, carry on the family name. When my brother got the autism diagnosis, all of those hopes went out the window. Whether he realized it or not, he had lost his expectations for his son, and in doing so, he switched over those expectations to me. Which is a tricky position to be in. You're still the daughter who he feels like he has to protect, but you're suddenly the son carrying on the family responsibilities. I love my father and value his wisdom and advice. And I think because I'm not a daddy's girl, my mom and I are unusually close, which I wouldn't trade, but part of me misses being a daddy's girl.
Anyway, I thought this might give you some insight into what may be going on in your DH's mind, whether he realizes it or not. I know my dad doesn't realize it consciously. He might be reacting more to this recent diagnosis than you realize though.