Great OP. So if your DH wants to take you all to Disney, the only words you need are, "Sure thanks." If your mentality blocks you from doing something like that as a family (and your kids will want YOU there), then really what is the point of anything? There will be thousands of families there and believe me, very few of them will have wrangled over who pays for what.
As for the "trophy wife" comment, maybe give that a little more thought. Where I grew up, we were mainly self-sufficient food-wise because that was how it was. So when my dad brought certain supplies home, did my mother say, "No DH, I'm not taking any of that meat / crop because I am an independent woman and don't need to be provided for. Ok, I can't be working outdoors as you do for 12 hours a day because of OUR children, but no matter! I can still get eggs my own eggs and make my own bread and I will survive by my own means. I am independent. Be off with you DH!"
Your working hours are also restricted by having had children, in a way that your DH's have not been. Ok, so he's bringing in money, not supplies, but it's the same thing really. You are in an unusual position in that you have your mum living with you to look after the DC while you work for your 20-odd hours. Most women don't have that option. What do they do?
I hate to see women put themselves down as "lesser" because of the reality of raising children and their earning potential taking a hit. Why would you think for one second, you are any less worthy in terms of family finances?
What matters is mutual respect. Co-dependency is a strength if there is mutual respect. My mother was one of the strongest women I have ever known. She knew who she was and what she was about and she had nothing to prove. She's my role model actually.
Your money does not define you -it's irrelevant. Let your DH support you if he wants to - you are the mother if his kids, first and foremost and above all else. What is more important than that?