You can't save them

This sounds like such a trite affirmation but it's true, often painfully so. 

People aren't projects to be fixed - and more importantly, even if they were- you can't fix people who don't want to be fixed, or people who refuse to admit they're even broken.

Take drug addicts for example - the best thing a heroin addict could be told is "No"(that and a paid trip to a high quality rehab but let's not split hairs here). Agreeing with a heroin addict's every demand is being complicit in their self destruction - knowingly or not. Your only path forward is aggressive indifference built on your own ethical framework or removing yourself from the equation entirely, should that option be a viable course of action. 

And it's hard to say no for some people - people pleasers, or simply those who the person they're saying "no" to might be someone close to them. A friend, a lover, a family member - someone whose influence on the psyche makes emotional objectivity difficult. 

It's hard to watch someone you care about self destruct, and the urge to save them from their own self destructive decision making or lifestyle is all too human - but as just and moral as that empathy is, it's also self destructive on your part to try if it becomes apparent your influence is either unwelcome not not effective. 

Letting go is the hardest thing anyone can learn to do, and it's a lesson I've had to learn many times over before it stuck. But it has stuck. 

The worst part is that the time you spend on trying and failing to save those who don't want to be saved is time you could be spending working on yourself, or helping those who both need, require, and are asking for your help--- and those who are willing to put in the work to better themselves, even if they need a bit of help along the way to get to that point. 

Doing good work is important - being conscientious of your ethics *is* important, but just make sure your good work translates into good actions as well. Execution matters just as much as intent, and when possible you should strive to stick the landing.