The boss's remark was dumb. But, we all say dumb things sometimes. Often we don't realize how our remarks affect others. I believe that s/he was trying to give you some guidance, but it was not done in a productive way. Please take these words with a grain of salt, put the sting aside, and focus on the fact that there was probably a good intent there.
To turn this into a positive experience, ask people you trust and respect for constructive feedback on your wardrobe. They may be able to give you helpful suggestions that you can benefit by.
Elinor Robin, "The Relationship Mediator," has more than 18 years of experience in mediation while working within the public and private sectors.