it's cheating if he's one leg on two boats
for 背叛...if you think of relationships in a 主僕 relation...then it's 背叛...
or it's just suitable for each other or not
i dont think that's 背叛 ba...if the guy was honest abt it...and broke up after he knew that he loved that other girl...
for me see..i wouldnt see it as 背叛..and i could still be friends with him lo...
i dont know ne..it all depend on ur point of view ba...
but u know..the world is full of controdictions...
there's really no absolute truth or falsty...
i guess we all have to get use to it some day...