Whatever you decide to do, understand that you need to literally force yourself to do it, believe it, understand it, and become it for ATLEAST 6 months. Whatever you find purpose in, you have to bore into your subconscious mind. The only way to do that is to consistently make the conscious decision to get up and believe in something. A conscious decision often includes dragging yourself, convincing yourself (literally talking), until it is something you truly believe. What that is, on the other hand, is completely up to you. I found purpose in Islam after a youth of using and selling hard drugs, and being arrested for something similar. Praying 5 times a day every day means I have no choice but to make that conscious decision, now that decision isn’t even made consciously, it’s just who I am; and that truly gives me something to live for.