Abu Hurairah (May Allah be pleased with him) reported:
A man said to Messenger of Allah ﷺ: "I have relatives with whom I try to keep the ties of relationship but they sever relations with me; and whom I treat kindly but they treat me badly, I am gentle with them but they are rough to me." He ﷺ replied, "If you are as you say, it is as if you are feeding them hot ashes, and you will be with a supporter against them from Allah as long as you continue to do so".

[Muslim].

وعنه أن رجلاً قَالَ : يَا رَسُول الله ! إنّ لِي قَرابةً أصِلُهُمْ وَيَقْطَعُوني ، وَأُحْسِنُ إلَيْهِمْ وَيُسِيئُونَ إلَيَّ ، وَأحْلَمُ عَنْهُمْ وَيَجْهَلُونَ عَلَيَّ ، فَقَالَ : « لَئِنْ كُنْتَ كَمَا قُلْتَ ، فَكأنَّمَا تُسِفُّهُمْ الْمَلَّ ، وَلا يَزَالُ مَعَكَ مِنَ اللهِ ظَهِيرٌ عَلَيْهِمْ مَا دُمْتَ عَلَى ذلِكَ » . رواه مسلم .