This is called sunken cost fallacy. The only way to get rid of this literal burden is to either force yourself by will or by means that would ensure you cannot access it. Here's some tips to rid yourself of the game or temptations to start playing again.

Are you playing Runescape with no schedule or putting the game above activities that you used to enjoy, family time or work? A lack of control is an early sign of addiction. In addition but not limited to: decreased socialization; abandoning commitments, irritability, and anxiety.
Playing on more than one account at one time.
This is seemingly a common occurrence with most players thinking they're optimizing their time. Some I have seen on up to eight or even twelve accounts at once. In reality multitasking lowers your intellectual capacity over time to problem solve in a singular environment and is quite detrimental to your intelligence. From an outside-looking in perspective the player feels the need to fill time but doesn't know anything but the game so the game itself entrenches, shoveling out other hobbies. Essentially becoming their life.

Rome wasn't built in a day. In fact Rome wasn't the splendor it's recanted to be until after Octavian founded the Roman Empire post Republic. In essence, things take time. You won't quit smoking on day one, I'd know. It's a slow process. Just like how Rome was sacked multiple times during it's reign you're going to relapse. Quitting Runescape and removing it from your life however is much easier and there are steps you can take to completely remove Runescape from your life. A good option would bePlayer Auctions. You cansell your account for actual moneynot only as a final f-u to the company that ruined some of your life but also get a little actual profit out of it in the process. I did it and it works.

Create a new routine in which you take care of yourself instead of some company rule you. You're going to feel so much better and have so much more control. Other people will laugh at you but most will be projecting within that cycle of cynical addiction within the game. Just know that you've won and they're losing, refusing help and going nowhere. I hope this wakes some people up.