Many would argue that one of the benefits of having a decent relationship with your relatives is that you can hopefully rely on them for help when you're in a tight spot. The thing is, certain kinds of support are always going to come with terms and conditions, even with loved ones. Just because somebody accepts a person as family does not mean that they have a high level of tolerance for their behavior. Establishing boundaries is vital with certain individuals.
Unfortunately, those problematic family members who most would rather keep at arm's length are also the ones who are most likely to get themselves into situations where they have no choice but to ask for the help of those closest to them. It leaves their relatives with the dilemma of how much they should help without getting their life taken over by their behavior and demands.
While it may be true that sacrifices have to be made for family relationships now and then, it is important to know where to draw the line. Otherwise, you can end up in a scenario that is painful to get out of.