As someone who experienced forms of abuse in my childhood, this scene has never failed to get me. I remember the first time I watched it and realized what Robin Williams' character (Sean) was doing. I immediately started shaking. The role Matt Damon plays, (Will), and his response in this scene, is so very real for me. This scene reaches that child in me and holds her, and I hear it too - "it's not your fault, it's not your fault."
I don't think I yet believe this truly, deep down, or else I wouldn't do some of the things I do - whether it be negative thoughts on repeat or actions that go against the flow of happiness available to me. It's difficult to get through such heavy layering, to break through such thick barriers as the characters manage to do in this single scene.
Maybe, each time I rediscover this scene, it makes a crack to crumble, to wear that wall down a little bit more.