Ick, yeah, I would drop your 'friends'. Real friends don't use people as ATMs :/
Honestly, I haven't run into this much, as most of my friends know that just because I'm an escort doesn't mean I'm rolling around in cash. However, I did have one friend (an ex-escort, actually) who was constantly asking me to throw him large amounts of money to cover unspecified things. I would continually tell him 'no' and that I was just barely covering bills (plus, he OWED me money) and his response was, "That's fine, I understand. Hey, throw me 20 when you get a chance, thanks."
Um.... no.
Honestly, people like this will always be trying to get money out of you no matter what you do for work. It's better to just not have them around. If they're gonna drop you because you aren't paying for THEIR bills, then good riddance to them, I say :/