Here are some questions to ask yourself that will encourage you to set mature boundaries so that others can accept the consequences of their own actions:
Whose responsibility is this, really?
Am I really serving this person by suffering the consequences of their actions for them?
What will happen of this pattern continues on forever?
How will this person benefit if I refuse to suffer the consequences for his actions?
How am I sabotaging myself and other concerned parties by taking too much responsibility?
Stop taking on unnecessary responsibility for other adults and require them to deal with their own actions. Only then can they learn from their mistakes, and be motivated to avoid making them again.
Let them reap what they sow.