Existing as half a human

I made this thread because I didnt know where to go or what to do so I'm just putting things out there.

I find myself feeling like I'm missing a part of myself every day and seeing the people around me and how people go about their days and just everything that they do and I find it impressive but exremely daunting because I find myself incapable to reach the level that they are at even when i have a "happy day" and commit to it to the best of my ability. I don't know what to do and how I can tell the people around me that I'm not as strong willed and capable and that this "thing" and these thoughts that I have in my head aren't just me being lazy and that I'm not "normal".