Personally I'd give the guy back his pin and/or lavalier! Just out of respect...ya know! It's hard enough being through with a relationship let alone having a reminder...especially one that has no meaning to you (his letters/pin).
I was promised by a non-greek. I kept the ring but I later traded it in for a bigger diamond on a chain LOL!

Hey, I paid for most of that dang promise ring anyway!!!
My mom still has my father's pin...I think that's really neat. Maybe someday I'll have my own Sig Ep pin (sigh)!
Sisterly Love,
Hootie
PS. I'm semi-starting a relationship with a Sig Ep (my first Fraternity boy experience). So in the next few weeks or month I may be asking you all for help or advice! Wish me luck

:P
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What do you get when you cross and Alpha Omicron Pi and a Sigma Phi Epsilon? A beautiful Chi Omega!!!