My children are mixed race as is my younger sister and lots of cousins. This has been discussed for years. Some mixed race do have a superiority complex due to the media, culture, colorism and fetishism (by both black men and other men).
Even down to being called a coconut or becky with the good hair. However, op you have internalised so much of this, if you don't let yourself be fetisized. If you don't be superior, if you don't generalise and put everyone into one group, you will find it alot easier to navigate. Not saying you feel superior by the way.
One daughter has the hair type that grows very long and can be straight or have beautiful curls. The other has hair that was long but thicker, not as easily straight and also beautiful curls. I do not allow others to praise the straighter texture hair only. All these little things add up. The straighter hair one is also the lighter one by a few shades. These things are insidious and start from birth.
You have heard and seen these things your whole life and they have affected you, so get some therapy.
However avoiding mixed race people is wrong, some of my cousins were bought up in a white vacuum and so when talking to them, you would think they were white but so what. They are still mixed race and still know and appreciate both sides of their culture. Too much reliance is placed on whiteness or blackness depending on where you live, grew up and your accent and what interests you pursue. Just because you grew up or like the theatre does not mean that you are white now and just because you like grime does not mean you are black. This is the influence of racism and colorism that likes to group people. None of us should allow this to happen or go along with it in any way shape or form.
White people can like grime or opera or both. Mixed race people can like grime or opera or both. Black people can like grime or opera or both.
Mixed race people are fetisized just like black girls and women are. What you say about leaving a club is what many black women will say and also men thinking they are easy.
Your problem is that people of all the ages can be unpleasant but you are doing yourself no favours if you cut yourself off from your own race or the mixed race part of your race. You won't like everyone. No white person likes all white people and no black person likes all black people. You have been unlucky in the ones you have met but you won't change that if you carry your opinion on. You have reinforced your way of thinking instead of challenging it.
My sister, daughter and cousins and lots of my wider family, would be upset if they knew that you would not be friends with them because they are mixed race. They are so different in education, outlook and personality, just like other people and you would surely find common ground with at least one person. From private educated, now a professor and still battling prejudice on his campus and towards himself even though he is a professor because he is younger and mixed race, to living in a council house loving to club and having children who street dance and has African, afro carribbean, white and mixed face friends, very socialble but not ambitious and happy to coast through live, also great cook and great baker. To a great artist of pots of mediums but not sociable, very hot on colorism as has felt it but would be friends with anyone if she could be bothered to make friends, as happy in her own company. To my builder cousin who mixes with everyone, loves the pub and the footie.
These are a snapshot of the mixed race people in my family,all so very different so to shut yourself off from making friends with other mixed race people is to shut yourself off from a hell of a lot.
I think that you focused too much on them having a superior complex, some do, some don't, but don't focus on that, please focus on all the genuine people put there of any way including mixed race. Remind yourself if and when you come across that attitude, that it is not their fault if they are like that as they probably had a white mother who praised their looks and hair and skin tone as did happen alot when mixed race kids were mostly born to white mother. Or a black grandmother who internalised colourist and told them they were lucky to be lighter and have good hair or a not so wide nose. The last 35 years a lot of mixed race kids are born to bame mothers and their experiences will be so different because of this fact alone.
Remind yourself that racism and colorism is the roots of any superiority complex and this was taught to them comments about good hair, nicer features, nice skin. Growing up in a white area and passing or getting better opportunities as mixed race is simply more palatable to white people. Look at film, programs and media, modelling, etc. Mixed race people were accepted first and put forward more because they were more acceptable than a darker skin. Simple as that.
This is what caused the bullying many describe at school from black children as mixed race and black were pitted against each other and black people put at the bottom. Change your outlook to rally against this. Say no and do not go along with it. The colourist and classification. Many black actors still only choose their love interest to be white or mixed race, at a push light skin black and these attitudes lead to the superiority complex you spoke about, ostracism from black people who are sick of it, etc. You are caught in the middle of the effects of Racism, prejudice and colourist.
Yes colorism is rife in black communities but lots is being done to stamp it out, just like the work clearly needed to be done on racism. People think the UK has no racism compared with the US, but it is ongoing and insidious. Subtle covert, daily ongoings of micro aggressions and bad jokes. Brexit at least makes it more overt and actually you know more where you stand.
Choose to have nothing to do with this, so you found some with a superior attitude, find others.
I understand what you said op and I did not think you are racist, I think you are simply navigating your life and have had bad experiences and clearly little guidance on navigating it from your parents. You need secure parents to bring up secure mixed race children. It starts at home and your identity has been affected because of living in a vacuum like you said both sides showing racism.
I hope you can muddle through op and work on it as it will change and you can make friends of all races, especially mixed race and black if you want.