Just for the benefit of others:
In the UK we have schools delineated into the following categories:
Comprehensive/State schools - these are the equivalent of "public" schools in other countries. Free schools paid for by the state, where quality standards are geographically variable. They do all follow a national curriculum though.
Grammar schools - basically "free" private schools that require kids to pass exams to get into. the Labour Party has been trying to destroy them for years and the quality is generally very good. They do not follow the national curriculum and thus the quality of education is more highly optimised towards excellence.
Private schools - same as the above but parents pay through the nose to put their kids through them.
Public schools - typically the reserve of the kids of the rich, celebrities, royals and those with aristocratic lineage (dukes, barons, earls etc).
---
Aside from the fact that your friends are utter dicks (find new/real friends bro), is it really that surprising that some people don't hold the same regard for the value of education as you do?
You should read more about UK history, and how Thatcher's war against the labour unions basically created a social rift between the wealthy and powerful in this country and those without. The ramifications being the sentimental shift for much of the population, away from aspirations of social mobility, due to the increased perceptions of hostility towards the educated and and wealthy classes of society. This problem was never really solved and a lot of these sentiments run directly into the divisions we see today with Brexit etc.
But I don't even think this is part of the problem with your friends either.
Generally speaking, you don't get into public school unless not only are your parents are well-to-do, but also whether you live in the relevant catchment areas, many of which are insanely expensive for most people to afford to live there. Maybe your family's been resident in a qualifying area for a very long time, i.e. before globalisation, immigration and population growth pushed up the value of the UK property market to astronomical levels over the past 30 years?
Either way I think it's useful to acknowledge at least a certain amount of privilege having the luxury to have attended one of the most prestigious school-groups in the country.
Still doesn't justify the shit your friends were throwing at you around the dinner table though.
My advice to you; consider expanding your social circle a little wider. Ethnic migrants, whether 1st, 2nd or greater generational, are great friends to have since they don't bring with them the same cultural baggage when it comes to attitudes towards education, and for many actively value it more than you probably do, given that their families were entirely willing to sacrifice leaving their homes, families and people back home to prioritise it for their kids. You'd probably fit in quite well among people like that, of an equivalent social class to yourself (in terms of education level and professional experience).
Chin up mate and stiff upper lip as they say...
"You'd probably fit in quite well among people like that, of an equivalent social class to yourself (in terms of education level and professional experience)."
Wait, is your advice really 'stop hanging out with jealous proles'?
Please be sarcasm. Jesus Christ.