One of my friends always send me many gifts. I want to say her to stop sending them. I am writing a letter to her. But I am unable to find how to write her politely not to send more gifts so that she should not feel bad.

Please help me!

Just tell her that if friendship is based on trust and loyalty. She shouldnt send you so much gifts because true friendship is not based on items.
I am sorry I can't write her straight forward not to send gifts or telling her about friendship etc. She is my friend but she is of my mother's age. There is more respect than such kind of friendly closeness in this relationship. That's why I want her to know how burdened I feel everytime she sends me something. I want something very polite expression to convey my message to her.
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A possibility is first to write her how much you appreciate her kindness and care and how grateful you feel about them, and then to tell her she needn’t have the trouble of sending all those gifts because this surplus generosity really makes you feel uneasy. The problem is that she might take it as a polite acceptance rather than a polite refusal and proceed with her gifts. But I think there is a way out of this: if you repeatedly write such a refusal, it will become clear that you really mean it and not just want to be polite.
However, everything depends upon the situation here.
The nationality and age of the gift-giver would affect the choice of words.

Thanks a lot An Attempt!

I think your suggestion is better and will work to help me out.

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