Looks like they're not meant for competitive gaming. Maybe you should stop playing with them. You can stay friends, but you don't have to have them ruin your experience.
Alternatively, show them this topic. Make them feel bad with your well, thought-out words of displeasure. Maybe they will reflect upon it.
My oldest friend I have mentioned, he really only Bots and nothing else. He just bots and sells his gold to make like 30 real dollars a week in gold lol [I would like to point out I personally find botting or even gold selling in MMOs rather despicable].
Not to mention that it's against JaGeX's rules, and illegal. I don't really like that company, but they don't have bad rules.
Don't worry Summoner. Sona_Buvelle will protect you. http://i.imgur.com/xx0hSNV.png