"Can't stop spending" is not a good thing to be able to say.
But really, it's impossible to say anything without knowing how much of your DH's salary goes into running the house. If you get to spend at least 50%, on average, of your salary on clothes just for you - not even on clothes for DC, days out, trips to soft play, dinners out etc - every single month, it just sounds excessive.
I don't ascribe to what other posters are saying about buying clothes being boring. I buy loads of crap over a month, between clothes for me and DC, books, stuff for the house and all that, that plenty of other people would see as a waste or should be saved instead. But 50% at least of your salary on this stuff is a hell of a lot.
Either your DH is paying for everything, or you've got the ability to spend £300 and save £300, which is surely still ok?
How much does your DH spend?