Should I get rid of this dress?

When I bought it, it was an evening dress, because I didn’t have any evening dresses to wear, in the case of special occasions. It really upset my mum that I bought something so pretty for myself, so much so that she made bitchy comments about how people in her day didn’t waste money on such things and she smashed a wine glass. It’s sort of ruined my enjoyment of owning a beautiful dress and I have nowhere to wear the dress. Should I keep it, just in case, or give it to my fiancé’s sister? On the other hand, I don’t want to give in to my mum’s jealousy.

Should I get rid of this dress?
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