Please help!

I know how 당신 feel =/ this guy that I used to like flirted with loads of girls even after he said he loved me, and it made me so jealous that i scared myself!I started to hate the girls he flirted with...but I should have hated him. I also found out that he had a gf, and that he was just stringing me along....he still tries talking to me but i refuse to socialise with a bastard like him.
Jealousy can be one of the most unpleasant feelings ever,not only do 당신 feel guilty with yourself for feeling this way but also 당신 feel that 당신 can't tell anyone because they will think badly of 당신 :S but hang in there :)
Eventually 당신 will forget about him, and someone will come along who is perfect for you! So there is no need to be upset :D also 당신 shouldn't worry about being popular! I used to worry about it all the time (back when i was in school :L )but honestly, just forget about it and do what 당신 want to do, you'll be much happier.
So, my 조언 to 당신 would be to 옮기기 on, start up some new hobbies, meet new people and, should 당신 find someone else that 당신 like...tell them! Because we only get one life and its a fucking short one, so 당신 may aswell give everything you've got to make it a good one!
I wish 당신 luck :)