Why is self-esteem important to your overall mental health?
Well, imagine the opposite. Imagine having no self-esteem. Imagine that you don't regard yourself with any esteem, that you either lie and cheat and steal, or you were always playing the role of the doormat, doing for everybody else and never doing anything for yourself. What type of mental health would you predict?
Take both cases. Take the first case. You lie, you cheat, and you steal. You have no self-esteem. You can't esteem yourself, hold yourself in high regard, if you are making a mess of your character, your personality, by your choice. What emotion would you have toward yourself? In private you're going to pretend it's self righteous: "I deserve this stuff that I stole and I can tell lies if I want to. Everybody is corrupt." People who are corrupt like to see the whole world as corrupt because they don't want to recognize they have choice, free will. But when they look in a psychological mirror, they will feel self-disgust. Now, that case doesn't lead to mental health. That leads to emotional and behavioral problems. It leads to feeling hatred and envy toward anyone else who leads their life in a healthy manner. So you don't want to go that first route of lying, cheating, or stealing. You want to treat your own subconscious, your own mind, your own character, well.
What about the second route, the more common route? "I don't want anything for myself. I just want to do for everyone else. There's no self. You're humble. If you accomplish something great in your life you say "Oh shucks, it was just luck." You keep putting yourself down. You won't esteem yourself. You won't value yourself. And after a while you believe it. You believe that you are not a value to yourself. And after a while you start to feel bitter. You feel depressed because there is nothing for you in life. You're doing for everybody else and that's supposed to bring you pleasure; you see your husband getting on with his life because you're a slave to him, you're a slave to your kids, you're a slave to your boss, you're a slave to everybody and you'll never accept anything in trade from them. You treat yourself as worthless and then you wonder why other people treat you as worthless and why you don't have any self-esteem. It's a recipe for depression turning into a bitterness.
So many times in therapy, and I'm sure therapists around the country would agree, I hear "You know I've spent my whole life doing for everybody else. I'm sick of it. I want something for myself, but I feel so guilty when I say that. I don't want to be selfish!" You need some selfishness, not only some selfishness, you need a lot of self-valuing, respecting your mind, building yourself into a healthy individual. This is not a me-only person. People usually equate selfishness with that and that's wrong. It's essential to value yourself, to be selfish.
Answering the question "Why is self esteem important to your mental health", because self-valuing is the source of mental health. It's based on your own choices and your own actions. You earn your own mental health, so work towards that end. You want to get a sense of self pride, not because everyone pats you on the back with unconditional love and tells you you're wonderful while you've done nothing to earn it, but because you've made the choices and have taken the actions in your life that have earned you an invaluable sense of self-esteem.