It shouldn't be about money. A friend should be a friend regardless. No one should have those sorts of expectations from you. I've always struggled financially, but I've maintained many friendships. I've never asked for favors and when I was doing ok, no one ever asked me for favors. Friends are just there for one another, they help when they can, emotionally or other and do it because they want to, not because they feel they need to.

Sadly, I had to move and literally ALL of my friends are long distance now, but we still talk, fb, text, phone etc... all the time. I will say however, I do understand what you are talking about as I have toxic people in my life as well, and sadly... they are family. :/