This is the most obvious and widely accepted answer. And it is not hard to see why. People's behaviour and personality are based on their thoughts. The way they think is the way they behave. And thus, most often than not, we are our thoughts, or as perceived by others.

This is the complex part. Our actions are surely derived from our thoughts. But, weirdly we also have an eagle's eye vision of our own actions. We feel regret, feel wrong, or right about the way we think or behave. 

If you really think about it, and truly try to understand how you work. What you will realize is, that you have the power to disconnect from your thoughts and look at yourself as an observer. You aren't your thoughts. Your thoughts are but a part of you.

Let me try and break it down further for you. Are you your teeth? Probably not! Teeth are a part of who you are, but they hardly impact your day to day life. Until, they start aching, or if there's an issue with them. You truly understand the power of your teeth once you feel its pain. In the same vein, a broken brain that spews dillusional thoughts of self-hate, work in the same way as a broken tooth. You can't live a happy life with an aching tooth, you can't live a fulfilling life with a broken mind.

Meditation is the way to finding your true self. When you see yourself as a third person, are able to understand every aspect of who you truly are, and then let go of the damaged and broken thoughts. That's the way to salvation and leading a healthy happy life. Don't let the aching tooth ache, treat it, it's possible. Just seek the right guidance, that's all!