lovefooled
Someone fooled by love, someone who has been cheated on, or someone who loves someone, but isn't loved back.
Take this song as an example:
The Cardigans - Lovefool

"Love me love me
say that you love me
fool me fool me
go on and fool me
love me love me
pretend that you love me
leave me leave me
just say that you need me"

or

"Dude, you've been lovefooled."