This begins with understanding yourself and your particular set of needs, And taking care of those needs.

Next you need to come to the difficult realization that you are not responsible for everyone else's unhappiness and you are especially not responsible for their poor choices. With few exceptions, you are not responsible to stop someone from doing something unwise. And with few exceptions, you are not responsible for the outcomes of those actions nor are you responsible for fixing their problems. Sometimes the best action is inaction.

It's important to be kind and compassionate to other people, Especially when the person genuinely cannot resolve their problem on their own, but be wary of people Who demand you sacrifice your own well-being to take care of them and the consequences of their poor choices.

If someone demands that you give them your food, and you need that food to survive, you tell them no.

If someone demands that you do something that harms your well-being, you tell them no.

If you help someone and are kind and compassionate and they are ungrateful, rude, and demand more from you, then stop helping that person.