I know it may be a bit controversial here but myself and DH have completely separate finances. We share bills and that is it. We may mention but we don't really consult about purchases unless it's something like buying something for the house for example.
We receive exactly the same amount salary wise.
DH has made big purchases in the past and not "consulted" me in the sense that he's not asked me if its okay but has spoken to me about it. I'd never veto what he could spend his money on. For example last year he bought an expensive car that I though was a bit stupid but as I say, it's his money and providing he can still pay for what he needs to I don't tell him what he can and can't do.
There are a few reasons we do this, we get on well day to day but our likes and interests differ quite a lot. My husband has older children and I didn't want to join my income into their maintenance/costs, and I was financially, physically and mentally abused for years by an ex so I love having the freedom of my own money.
Anyway, mentioned to DH the other day I want to do an expensive holiday next year with our joint DC (we will also be going on holiday all together somewhere DH likes), it is a holiday he would HATE and have absolutely no interest in going on. But it is a once in a lifetime kind of thing. I'm happy to go alone with our DC. However, DH is complaining now that it's way too much money and I shouldn't go. To be clear it would be paid solely by myself and it won't affect us in any way, no more than him buying the car mentioned above for example.
Aibu to just do it anyway? I know he'd not actually prevent me from taking DC I'm not worried about anything like that. But he might grump a bit.