...like...what to do?

well you ca do 1 of two things 1. give it back kindly and say it was a nice thought but you don't need it or2. sell it on ebay or sumfing like dat

If you're concerned how your roommate will react, I'd say be straight with them about it. Otherwise you have a purse you'll be forced to use just to make someone happy. As a rule, doing things you don't want to do in order to please someone else leads to problems.