Can't Give A Cookie
Something I heard today really resonated with me, and maybe it will help you also put things into perspective.
YOU CANNOT GIVE WHAT YOU DO NOT HAVE.
For instance, your friend wants a cookie. You cannot girl her a cookie if you do not have one.
This works with everything in life.
YOU CANNOT GIVE LOVE IF YOU DO NOT HAVE LOVE YOURSELF.
It really makes you wonder about those people that are giving others hate. It makes you wonder what they are feeling on the inside. They probably are feeling hate, remorse, sadness, depression, or jealousy on the inside.
It is important to take what people say with a grain of salt. If somebody is treating you badly, just step back and realize it had more to do with them and not you.

This is why SELF LOVE is so important. You need to love yourself first in order to love others. You need to treat yourself nicely in order to treat others nicely. Work on yourself, do things that make you happy. It is not selfish because it will translate in how you treat others.