Why do i get so jealous the fact my guy friend flirts with other girls????????

[sweeto]

I am 20 years old and i am from pakistan anyways i use to cyberstalk this guy alot and he is also from pakistan he's 25.he never had a girlfriend.he really wanted to go out with me but i didn't and for that reason he became very rude and upset with me.i even sendes him my picture he wrote u look good.i still use to bother him alot and he use to get very annoyed.anyways i took revenge from him by bothering him because long time ago he showed his hairy dick to me and my friend in the park.the other day i went his facebook profile and he's standing with a white girl and he's holdimg her arm she's wearing tonk tops.he even flirts with a pakistani girl on facebook and he likes her picture.i get very jealous i don't know why by the way don't sayi lie him because i honestly don't.