He loves a woman but his mother disrespects her because of her origins
Question

                Assalama alaikum, ya shaykhuna, I have a
      question which is about my mother. I have a girlfried who is muslim and my mother and same
      of my family don't want me to get married to her because of her (tribe). They think that
      her tribe is no good and no one gets married to them. My girlfried and i came from the
      same country, culture, and relegion but different tribes. What did the quaran say about
      people who disrespect others for who they are. She said that if I get married to her she
      will disowned me and will never talk to her. I am so confused because the quran says do
      what your mother tells you to do. I think what my mother is doing is aneceptable in the
      quran which I'm not sure. I never talk back to my mother and i respect her opinions but
      what can i do and how can I handle situation like this what can I do please helb me.
     thank you
Praise be to Allah.Before we find out what the Quraan says about despising 
  others because of their origins, we should know what the Quraan says about 
  having girlfriends. Allaah says (interpretation of the meaning):
 Wed them with the permission of their own folk and 
  give them their mahr (dowry) according to what is reasonable; they should be 
  chaste, not adulterous, nor taking boyfriends [al-Nisaa 4:25]
In his commentary on this aayah, Ibn Katheer (may Allaah have 
  mercy on him) said: 
Muhsanaat [translated as chaste] means 
  that they should be pure, not indulging in zinaa (unlawful sexual conduct), 
  hence they are described as not being musaafihaat, which means promiscuous 
  women who do not refuse anyone who wants to commit immoral acts with them 
  Ibn Abbaas said: muttakhidhaati akhdaan means lovers. 
   Al-Hasan al-Basri said: It means a (male) friend.  
  Allaah has also forbidden this, meaning marrying her so long as she is in that 
  situation
Now that you know the Islamic ruling on this matter and are sure 
  that what you have done is haraam and sinful, we will now move on to what Allaah 
  says about despising others for their origins. Allaah says (interpretation of 
  the meaning):
O you who believe! Let not a group scoff at another group, 
  it may be that the latter are better than the former; nor let (some) women scoff 
  at other women, it may be that the latter are better than the former 
  [al-Hujuraat 49:11]
Allaah has not created mankind in nations and tribes so that they 
  may be proud and despise one another, but so that they may be distinguished 
  from one another and thus get to know one another. Allaah says (interpretation 
  of the meaning):
O mankind! We have created you from a male and a female, 
  and made you into nations and tribes, that you may know one another. Verily, 
  the most honourable of you with Allaah is that (believer) who has taqwa (i.e. 
  is one of the muttaqeen  the pious). Verily Allaah is All-Knowing, All-Aware. 
  [al-Hujuraat 49:13]
Ibn Katheer (may Allaah have mercy on him) said, in his commentary 
  on this aayah:
Here Allaah is telling mankind that He created them from 
  one soul, from which He created its mate  this refers to Aadam and Hawwa 
  (Adam and Eve)  and made them into nations, which are bigger than tribes. 
  Beyond the tribe there are other smaller units and divisions, such as families 
  and clans. An alternative interpretation is that nations refers 
  to the non-Arabs and tribes refers to the Arabs. All people are 
  equal with regard to lineage because of their descent from Aadam and Hawwa, 
  upon whom be peace, but some may be better than others in religious matters, 
  i.e., in obedience to Allaah and in following His Messenger  
  (peace and blessings of Allaah be upon him). For this reason, after forbidding 
  envy and scornful attitudes towards others, Allaah pointed out their equality 
  as human beings: O mankind! We have created you from a male and a female, 
  and made you into nations and tribes, that you may know one another  
  i.e., that they may know one another by referring to their tribes. Mujaahid 
  said that this meant by calling a person So-and-so the son of So-and-so, 
  from such-and-such a tribe.  Abu Hurayrah reported that the Messenger 
  of Allaah  (peace and blessings of Allaah be upon 
  him) was asked, Which people are the most honourable? He said: The 
  most honourable in the sight of Allaah are the most pious (those who have most 
  taqwa). They said, That is not what we were asking about. 
  He said: The most honourable of people is Yoosuf the Prophet of Allaah, 
  the son of the Prophet of Allaah, the son of the Prophet of Allaah, the son 
  of the Friend (khaleel) of Allaah. They said: That is not 
  what we were asking about. He said, Are you asking about which lineage 
  of the Arabs is most honourable? They said, Yes. He said: 
  The best of you at the time of Jaahiliyyah are the best of you in Islam, 
  if they understand properly. Abu Hurayrah (may Allah be pleased 
  with him) also reported that the Messenger of Allaah  
  (peace and blessings of Allaah be upon him) said: Allaah does not look 
  at your outward appearance or your wealth, He looks at your hearts and your 
  deeds.
Further information that is relevant to your question may be found 
  under #1805 and #1114. 
  We ask Allaah to bless us and you with strength and goodness, and to keep us 
  all away from that which is forbidden. May Allaah bless our Prophet Muhammad.