Are you depressed ? Talk to your friend about it. Are you depressed because you can't afford your mum's treatment ? "Don't come to me for money bruh". It frustrates me no end when I see this nonsense about not mixing finances with friendship. The lack of material understanding of suffering is so apparent in that stupid advice. Friends should exist not just to offer a shoulder to cry on, but also to lend a crutch when you have trouble walking. What conception of friendship puts one of the main drivers of despair and helplessness (financial troubles) outside the bounds of cooperation. Pretty sure the first person to say these words was a feudal lord to a peasant with whom he would otherwise enjoy a nice drink and lively conversation.
To any of my Toronto based chapos, if 100 bucks in cash can help you with something, I will be more than glad to give it to you.
I'm still pretty sure the saying is explicitly about things like giving someone a business loan or some shit. It's that a person whose a good friend isn't always the best business partner.