Thank you for all the views expressed so far. Those of you who doubt my "story", I assure you, I am a real person. There are no discrepancies. I have been deliberately vague to avoid giving out too much info, but if it helps, I have been married less than 5 years, have 2 children under the age of 4, and the issue of school fees / childcare costs arises because, while we are not currently paying private school fees, we do pay for a full-time nanny to care for our children while we work, as well as pre-school fees for our eldest.
For those of you recommending I seek legal/financial advice, please be assured that I have done that. My question is not about the legal/financial issues. It's about whether I am being unreasonable to think that I deserve more in the event of a divorce. I am genuinely interested in people's views and am not "catfish in". Sometimes these things are easier to talk about with strangers than close friends.
Lastly, there are lots of people on here suggesting that I have no right to any of the money he brought to the marriage because I make enough enough money to thrive without his support. But this is not about whether I need that money. Clearly I don't. However, I do think it right that I should receive some of it for the reasons that: 1) I contribute more - emotionally and in time spent - to our family life, especially the care of the children, and a 50/50 split of assets we've generated after our marriage doesn't take account of that. Rather than working out what the right split is, a simpler solution is for him to give me some additional cash on divorce; 2) We have settled in an expensive area (in part due to my husband's large asset base) and have had children who are set up to go to local schools. Thus my needs have changed as a direct consequence of our marriage and the fact that we have had two beautiful children. I think it reasonable that I should be permitted to meet these needs (i.e., being able to live in a decent-sized property for the area) without taking on the potential risks and stress associated with a large mortgage. Note that when I use the term "needs" in this sense, I don't mean absolute need, but rather reasonable expectations.
Anyway, there it is. I don't really know what I expected from this forum. I guess the answer is that I am being unreasonable and maybe that's right... although I feel quite a few of the comments have had more than a tinge of misogyny about them. Either way, I'm grateful for the input. Thank you, all, but especially those of you who urged greater kindness and respect when commenting.