u stop caring what people think, stop letting your ハート, 心 decide insted of your brain, and, most importantly, don't let people who've never let their ハート, 心 brake または ach answer 質問 like this!!!!
Run around with a シャツ that says "Poop Balls", bang buildings with hammers, mix soda with チョコレート syrup, and hang out with black people. (That was ment to be a refrence, not racist...)
Make a pact with the Devil to create a demonic spirit in the form of a girl who is your ex-boyfriend's absolute Dream Girl, and on the night where he is the most defenseless have her slowly torture him and feel pain that is completely incomprehensible for the human mind until he dies. ^_^
I believe only time will do that,by time あなた will forget,it will fade slowly. And even when あなた have no hope,something nice will happen. あなた just need to turn to the cheerful things. Don't waste your time on someone who will never understand your pure feelings.