If you want to quit because of an addiction. Then try break the habits. Do one thing you love doing that's not Destiny, at the exact time you would usually start playing Destiny. If you're occupied with something else that's not Destiny, you are less likely to think about it. It helps more if it's not video games altogether. Now if you want to quit just because you are upset with certain things going on in updates and what not but you are still having fun ingame then I think you are just thinking you need to quit even though you are having fun. Play until you feel burnt out. Then you can always take a break or stop playing if you get bored.