This issue resonates with me, too. My difficult situations do not involve friends, as I have always chosen my friends for their character and, to me, solid character definitely includes financial responsibility. We don't choose family, however, other than spouse and, arguably, descendants. I have five siblings still alive (one died), four of whom are financially irresponsible. They learned this from their mother, who is an "enabler" par excellence and is, individually, the most irresponsible of all. It is sad but true that my personal net worth is at least treble the net worth of all five of them, taken together.
The consequence of their decisions to live irresponsible lives has been a very high degree of estrangement. The specific causes of the estrangement are two: (1) actual requests for money, which I have come to refuse due to bad experiences early on; and (2) anticipated requests for money, which I simply don't want to hear. I find that the second is more upsetting than the first, and this has caused me to cut off contact for the most part. I wish I could figure out how to manage this better, but I can't. Who wants to socialize with a Financial Pig Pen? Not I.