I don't think I'm being unreasonable but welcome your take on things.
My partner is terrible with money and his wages never seem to last. He pays his share of the bills (rent, utilities) and then ploughs through the remainder at lightening speed leaving me to budget my money for the food shops / essentials for the rest of the month.
The thing that has brought this to a head today is something seemingly trivial. We needed something for the house and I found it online for a good price. This morning he announced he has bought one, I asked how much and he said £30 more than the one I showed him. It was exactly the same so a completely unnecessary over spend.
We've started buying Christmas presents for our DC and my DSC. I'll be staggering the cost (started in sep) but he's ordering everything all at once so he'll be skint again soon.
I never end up skint because I shop smart 
AIBU to be irritated by this, or should I mind my own business so long as he's paying his share of the rent and bills?