Praise be to Allah, the Lord of the Worlds; and blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions.
A Muslim's character who fears Allah is to have good relations with his relatives, and should not cut them off even if they treat with him unjustly.
Hence having the good relations is an obligatory act in Islam. The Prophet mentioned the best reward for the one who practices it. It is narrated in Sahih Muslim That A man said to Messenger of Allah: "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 (Blessing and peace be upon him) 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].
"Feeding them hot ashes" is a simile to the sin they are committing to the pain the one who gets pain when he eats hot ashes.
Dear brother do not give any attention for their bad treatment; try your best to be good with your uncles, hoping the good reward from Allah. Maintaining good ties with relatives causes blessings in provision and life as the Prophet said: "He who desires ample provisions and his life be prolonged, should maintain good ties with his blood relations". [Al-Bukhari and Muslim].
In a Hadith Qudsi Allah says: `He who maintains good ties with you, I maintain good ties with him; and he who severs your ties, I sever ties with him".
If your visit to your uncles can cause something wrong then do not visit them constantly. It is enough to visit them on occasion's such as the festivals, marriages, or visiting them for greeting on happy occasions or to offer condolence on sad times or visiting them once in a month or in two months. So that you would not be considered as the one who cut off his kin relations.
You may know that having kinship is not restricted to visiting relatives only. You may maintain good relations by talking to them over the phone, or by writing them a letter or sending them a telegram, fax etc. or you may send them gifts through friends or other relatives. There are many ways you may try. May Allah bless you and guide you to have good relations with your relatives. Allah knows best.