Fiancé is beyond selfish sometimes.

I'm pregnant, we're trying to save money because when the baby comes I can't cut my hours at work I have to go back full time. So my fiancé goes out with his mates a hell of a lot more than I do with mine, he's out till gone 3am most times which I think is a bit excessive. Now he's out, he's been out since 7pm (it's past 3am now) and he's gone to the casino. Gambling money we should be saving. Why should I be the only responsible one when I can't even cut my hours to be with our child after my maternity leave is up. But he can't still have his all night piss ups?!