"Anata wa watashi no bubun o motte, watashi wa sore o kaeshite hoshī!" what did i just say?

Bubun means a part of something. I don't know if it could be "You are a part of me..." or " You having a part of me, kaesu means to exchange or return something, I think..... Oh I see. Yes, I can get that idea. However, I am a native English speaker. I don't know that these sentences make any sense in Japanese. I have heard expressions like kokoro wo motte asobu "playing with (someone's heart) Maybe I am thinking of the last part as .... motte sono bubun wo kaeshite kudasai. I don't know if that is any better --- just grammar that I seem to have heard somewhere.