helping an old friend

so my freshman year college roommate has been hitting me up a lot lately. (btw we’re still in college) but she’s only asking for money. I was happy to give it to her at first bc it was just like $5-10 and she needed it. But now I realize it’s been a lot (like $80 just last month) and like Ik she needs it but I just feel used. I know I should just say no but I feel bad because she has said she needs the money for gas to get to work or earlier she needed 15 to get her medicine.

How do I nicely deal with this