My Gf is sleepin with other guys for money

I'm 21 and my girlfriend is 19, we've been dating for half a year now and I've slowly found out that she usually sleeps with some other men for money. Don't get me wrong we strongly have feeling for each other but she's always running into financial issues because of her drug addiction (greens). I have only just graduated from University and I'm in no position to always help her out when she needs money but I try to whenever I can. I recently told her I know about what she's doing and she assures me she's honestly only doing it because she's struggling financially. This is my first serious relationship and I hate that this is happening. Having no previous experience, I don't know how to go about it and would need advice from you guys.

Stop doing drugs, and have her get a job. What kind of woman are you dating?
These are terrible morals and values..

I really have nothing to add since this isn't a situation I would ever allow myself to be in.

I'm against giving ultimatums generally, but in this case, me personally, I would give one, "I enjoy being with you but I can't be with someone that's sleeping with people for drugs/money"

Obviously the problem here is that she wasn't even being upfront about this to you before, deceptive behavior. Not good.

I understand how you feel man. Once had alcoholic girl that I loved a little. Drugs might not be something you like but its her choice and some deeper issues might be behind it, not just addiction. So yeah if you want to help her then start would be to find out why she needs this escape and then deal with the root of the problem. Its easy to say stop doing drugs and start work and it might work but to avoid going back to old ways, some deeper soul searching could be needed. Like she could have messed up childhood or lack of motivation or morals, that needs to be adressed. Giving money wont help her. We all want that milion dolar to fix our problems. All prostitutes doing it for the money, its easyier and faster way than work to make a buck . Perhaps finding a true love could make her stop.

The issue is not that she's sleeping with others
The problem are her financial issues and the drug addiction