It's not wrong, but it's time to rethink how you two handle finances. The people above have a point - when income changes significantly, keeping it 50/50 stops being fair and becomes more a reflection of being too lazy to have the conversation than an actual equal split. The thing is, you're getting squeezed while he feels zero impact, and that's gonna breed a ton of resentment.
The conversation doesn't need to be awkward. Just tell him calmly that you two need to adjust because the situation has changed - it's not an accusation, just reality. You can try different approaches: split proportionally to your incomes (if he makes 70% of the total coming in, he pays 70% of expenses), or you cover different things (he pays for the fancy restaurant, you pay other stuff that matches your budget), or even agree on a fixed amount you can contribute and he covers the rest.
One practical trick that works well: put together a simple spreadsheet with your monthly expenses (rent, groceries, going out, etc) and check it out together to see what the total is. Then you calculate how much each of you makes percentage-wise. It's way easier to see things when they're laid out in black and white than arguing about it in your heads. It might seem overly unromantic to track everything, but financial honesty is just as important as anything else in a relationship.