Well, huge congrats on the job. Getting that is a real achievement for anyone who has been out of the workplace for ten years. Sounds like a great role too, with training, security, working in a team, with customers, very rewarding.
Your DP sounds bitter and resentful unfortunately, taking out his own professional frustrations on you, unable to see the bigger picture.
Going back to work after ten years, to something with high pay and status, is madly unrealistic for anyone. I've been a SAHM five years, no MH problems and have done things to keep my CV alive and I know I'd be lucky to get a 'first stage' job, two levels down from my previous one, in my field, as a way back in (partly because higher up jobs rarely come up nearby but I wouldn't get them at this point). Obvs in a different field I'd have to start lower anyway.
Worth noting that it's much easier to find jobs when you're in one, so having any job is the best place to start if you might want another one - though you don't have to want another one.
Having a PhD may become relevant much later, if you choose to develop your career. That's usual, even for very career-minded people in a specialist but non-academic field. They start at graduate entry level but rise later.
Having a PhD is an amazing experience to be able to pass on / influence your parenting and your discussions with DCs about their futures. You'll be able to engage with them helpfully, meaningfully, impressively, on research-related topics.
Was going to say that , if money and status are so important to DP, why is he not a professor, chief exec of a multi-national, partner in a city firm etc but you've answered that partly. Sounds like he hasn't really grown up and understood that life is not the same as adolescent dreams of life and career, that luck plays a huge part, at work as well as outside it, and that making the best of what you have is a real achievement. Perhaps one day he'll gain some maturity and lose some status anxiety? Not easy, does happen.