I don't think you're being unreasonable. I've been with my DH 10 years now, young couple brought our home at 24/25, currently pregnant with our first. We've always split everything right down the middle, into a joint account equally.. that includes car insurance, food bill, gas,electric, mortgage, council tax, life insurance etc etc, then Whatever is left of ours to do as we please with. If we decide we want to buy big something for the home, garden, holiday etc we both put equal parts into a savings account and buy it.
We've saved considerably to cover maternity leave so we can sub our joint account from the savings when I'm on leave, still allowing me the freedom to do what I wish. When maternity leave it up I'll be returning part time to my job (I'm quiet high up so can afford a small pay decrease) but once I am back earning I will again split it half ways. He'd never see me go without and vice versa.
She sounds very entitled but then also, you played a mugs game for financially providing for her including paying her legal fees especially after being together a relatively short time.
In saying that, I've always considered myself a very independent woman and wouldn't want a man paying my way, that way if anything ever went south I can cover myself.
If your home jointly owned?