There is no magic answer here.  Unfortunately people tend to make quick judgments based on first impressions.  This often includes an assessment of appearance.

Although it is unfortunate that people can be mean and prejudiced sometimes, I tend to think about it this way:

If someone does not want to take the time to get to know me and like me for who I am instead of what I look like, then do I really want them in my inner circle anyways?  Probably not.  Not to say that it is easy to operate this way in the world as I know it, in fact it is sometimes downright difficult, but that does not stop me from trying.

I am happy with myself and confident enough about myself to not take it to heart every time someone ignores me or doesn't give me the respect I know I deserve.  This does not work every time and we learn to develop thick skins.  It is also ok to let it overwhelm ourselves occasionally and seek comfort and love from our close friends and family, that's why we're here after-all.