boyfriend just flipped out at me

Okay so me and boyfriend have been together for nearly three years and most of the time he's and amazing loving boyfriend but sometimes when he gets mad about something he won't think before he speaks. Today he woke up and said I want to play a game online which you have to pay for, he doesn't have a debit card so i let him use mine and he pays me back for however much he spends but this particular game always fucks with my bank account and always takes the money out weeks later when I can't afford it. So anyway he asked and I said no and he just fucking flipped his shit. Told me to buy own shit from now on (which hurt cause I try so hard not to ask him for anything anyway) and called me a cunt. The one word I literally hate being called from him. And hasn't talked to me for about two hours now. I know soon enough he'll try and apologise but I'm so sick of him overreacting and saying mean things to me when he's mad, which to be fair isn't very often but still. I've tried to tell him that it's hurtful but he doesn't seem to listen. Does anyone have any suggestions as to what I should say/do when he comes to apologise?