I burnt all of my ex-grilfriends (I didn't burnt *them*...), those pieces of memory can only hurt you.
You can be sure of one thing: Your ex have another boyfriend, your teddybear is only a war plunder for her. The solution for you is only one: sex, a lot of sex, sex all the time, after 5 of 6 more gilrs all will go in the right perspective and your actual mood will come back only in your nightmares. Stay far away from that girl and have SEX. You're too young to miss your (sex) time in this kind of craps, and these are not times of endless love. One alternative is to lose a lot of time thinking at her with depression etc. , or to buy a gun and go to take back that little bear.