Sleeping problems... help pleasee? getting fed up :(?

im 16 , 17 in september... i split up with my boyfriend of 5 months about a month ago..and since then ive been having alot of stress problems as the problem with my ex is carrying on.. im finding out more and more about him and although i hate him he just keeps reappearing in my life.. but on a night i think its related to the stress what i just said above. but on a night i cannot sleep! ive re decorated.. moved my bedroom around and even bought a new bed.But whatever i do whatever time i go to bed i cannot sleep all the way through the night and im gettin fed up now ov being tired and warn out. does anyone have any ideas what i could possibley do because its gettin me really down. Thanks :) x