You need to explain this to him. why are you living with a guy whom you can't tell this? Is he just there for financial support? No? Then tell him so! Tell him that you need a bit of the security of having your own money. It gives you support, because that way you can at least safe some up for emergencies. DO safe some up for emergencies. There have been so many women that got thrown out by their boyfriends without a cent to their name. Even if you just safe 50 dollars a week it would be a start. I also get what you mean by just wanting some of your own money. I wouldn't always want to ask my guy if I can buy coffee or a t-shirt!
I'm sure he'll understand, too. Just tell him. Have a long discussion about why you want this. Make sure to take the night of from everything else to talk about this. It's really that important!
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"The important thing is to enjoy your life-
to be happy- it's all that matters."