My sister gave me Allison Dubois' book, "Secrets of the Monarch" to read. This is from the chapter on relationships and being your own best friend.
"People who always make promises but never keep them aren't valued by others.
On the flip side are those who burn themselves out living for anybody but themselves, and they lose themselves in others. I'm asking you to find a balance. It's okay to say no to people when you're spread too thin and it's affecting you mentally and/or physically. Boundaries are important in life, and those who never learn to create boundaries for themselves can become doormats.
Equally destructive are those who refuse to respect other people's boundaries and see the lines as invisible. They cross these lines frequently as they disregard people and hurt them by sucking the very life out of them. Everyone has know an "energy sucker" as some point in his or her life. I mean a negative energy that literally depresses you and steals your energy."
Good stuff Allison, look after my mother while I go and have 'doormat' tattooed on my forehead.