Bollox. This is 2018, where equality is strived for. I mean, I'll offer to pay, but if she says yes without hesitation that's a huge red flag for me. I don't like to set precedents, and her doing that just says to me that she's not independent and I'll end up paying for everything. Ideally, I'd offer to pay, she'd say no, then I'll be like "Are you sure? Alright then, if you insist, let's split" and I'd round my half up just for simplicity and politeness, so like if the combined bill was £37 I'd pay £20.