Tell her, there is a difference between: being nice to others, and being a Door-Mat.
These are 2 very different things.
2) Tell her, that being "nice" is fine... BUT, it takes WISDOM to DISCERN situations. And it takes common sense, to know... if you are just being used and treated like a door-mat, or not.
If you are being a Door-mat, then that is not about being "nice."
Being nice, also means.... standing up for herself, because it teaches others, about boundaries.
Niceness is multi-faceted. It is also about boundaries. You are doing no one any nice favors, by letting them treat you like a door-mat. It teaches them, nothing.
Your daughter is sensitive as you said.
And has empathy.
But, even with professional Social Workers... they HAVE to, discern what is appropriate or not. It is not just about being "nice" to someone. In order to help people, you also have to be able to say NO, or stop... them from trampling all over you.
Your daughter has to learn a sense of what is appropriate or not.
She has to, know herself.
She needs to, be herself and with that, learn to gauge, her efforts to people or not.
You see, being "nice" is either her goal, or her need to feel better about herself. And even if she is nice, not everyone will even appreciate it.
And, keep in mind.... that the person she is "nice" to... they do NOT even have to... return the favor or like it or appreciate it or be her friend.
That is the flip side to it.
A person, cannot MAKE another person, be what they want them to be. Just by being nice to them.
There is the reality, and there is the ideal.
But sure, some say just be nice and the other person will come around and change.
But, you cannot change everyone, just by being "nice."
If anything, all of this is a life lesson for her.
And it takes time to learn.
Or one day, she will use her strengths, toward a useful goal.
Not wasting it on people who are mean.
Your daughter cries about it.
Because, it is not turning out according to her ideals.
But you cannot change people or all people, just by being "nice."
One day as well, she will be someone's Girlfriend. And per boys... certainly the hope is that she is not just a people-pleaser who will do anything "nice" that a boy wants... just to please him.
Hopefully, she will become her own person, and know herself well enough that she will have boundaries for herself.
And then, she will learn to CHOOSE.... if she will waste her efforts on users or know who a real friend, is.
And knowing that... you cannot... change everyone.
She needs to learn, Self-Respect.
There is a time to be nice. And a time to walk away.
And not be a Door-Mat.
And it is something she has to learn. This is only 4th grade.
And you cannot control, if her classmates has older siblings or not or their ages.
You cannot make... someone be your friend. If they don't want to.
And you cannot please everyone. Just by being nice.
Being "nice" is not a tool. It is a quality.
And you cannot make... someone like you, by being nice.
My daughter is 10. Just finished 5th Grade. And is the oldest one in our family. And lots of her classmates has older siblings. But, she chooses, friends. She chooses. And she chooses according to character. Her friends are nice. She stays away from mean kids.
Your daughter, seems to want to please others even if she is being rejected. So then she tries to be nicer to that person hoping that person will like her. Some people, cling more to people who reject them or are not nice to them. And it becomes a vicious cycle.
ETA: Some people, just cannot "let go" of a person even if they are being treated wrongly and being rejected. And they just keep trying to be "nice" to that person.
It becomes dysfunctional. And they keep clinging... to that person.
- Then the other side to being "nice" and empathetic is:
IF your daughter always EXPECTS the other person to like her or to become her friend, whenever she is "nice" to someone else, then, being "nice" is not nice either. Because, she is expecting something... from it.
From the other person.
She cannot expect, that being "nice" is reciprocal.
Being nice means, just being nice.
It does not mean that something has to be done or given to her, in return.
Emotionally.
And being nice... will not "fix" other people nor turn them into what you, want.