In my book, Girlfriend 911, I talk about how every relationship you're in starts and ends with YOU. YOU have to be okay with yourself, you have to be connected to your Authentic, True self and you have to always be in your power. How do you do that? Create a set of standards for yourself and boundaries for those around you.
Respect your SELF, love your SELF be okay with YOU. If you are you'll never allow anyone to treat you badly, or take you for granted. Here's a great guide to SELF love by Louise Hay, check it out: http://bit.ly/1VaGIqK