Just do what makes you happy mate, if you're planning to play another game so you can forget about Runescape that's just stupid imo. You will still be wasting the same time but its just another game..
If you actually want to get rid of being an gamer etc start working in real. Get a job wich gets you tired and pays a little above average. Trust me; once you get the hang of it the only thing you will do is school-work-sleep. Not because you want to but you have too. You don't need a social personality to do this; just the discipline to work hard and wake up early in the morning or work in the night.
I quit in early 2014 and started working up to 18 hours a day sometimes (combining 3 jobs). I did that successfully for about a year. However; late 2015 I just started missing Runescape so started playing again like a month ago. Really.. If you've ever been addicted to RS you will always come back; which is fine. Because personally; if I don't play runescape I go outside to clubs and shisha louges and other stupid stuff where I just waste money.
This is my experience on quitting>playing>raging>quiting>playing runescape, maybe you can do something with it
Goodluck