I can say there is no way to avoid it once they have deliberately borrowed your money. In this case, you can just choose to lend and accept the loss of the money and the relationship, or you'll just give up on the relationship in the first place. For a person who wants to borrow money but has no intention of paying it back, I will not need the relationship, I will not lend it, and would rather lose the relationship than lose both.
everything returns to oneself and we can see the condition of a family to lend money, if the need is very urgent and important I think we have to use our conscience a little to help him even though we know the risks we will face.
but if you just borrow money without knowing the needs I think it's better to avoid and refuse in a way that doesn't offend.
money is not everything, family ties must be maintained as well as possible because basically humans need each other, it's not just about money and family are people who will see us later when we hit a disaster or in old age.