I know I'm not the one who originally posted the message. But I will speak to it, for anyone who's interested.
I still don't think too highly of myself most of the time, but it's a far sight better than what I used to think. I spent most of my teens locked away in a room - when I wasn't out getting trashed - crying and raging because the world hated me and there was nowhere for me to go. I was stupid, ugly, fat, had no use in life. I tried to end it all once when I was 15. I had become that tired of the life I was living, and that convinced that what I believed of myself and the world around me was the truth.
My twenties weren't much different, except that I was no longer in high school so I had to move out of my parents' house and drag myself through the world feeling that way. I didn't get a mental health diagnosis until I was 30 (four years ago). It should have happened long before that.
It's WORK to change that thinking. It doesn't happen over night. It's not some psychic change for most folks (some say it is, but very, very few) where they just wake up in the middle of the night and think "I'm done thinking about myself/the world this way!" and that's really it for them. It involves challenging those thoughts every time they come up, or every time you are aware that they are coming up. For awhile all you might be able to do is be aware of them. That's the worst part because it feels like torture. But after awhile it is possible to start challenging them.
Example: "I'm fat/ugly."
Me, to myself: "Who says? And compared to what? Whose standard am I comparing myself to? A body can look many different ways. This is the way mine looks. I might not be 100% okay with it right now, but it's gotten me through this life and that's something to be proud of."
Example: "I'm a failure. I didn't do it right. I didn't do well enough. I'm not good enough."
Me, to myself: "I did my best. I honestly did my best. There was nothing else I could have done."
And just because I'm challenging the thoughts doesn't mean they don't come back, or keep playing over and over again on an endless track in my head. And when I notice that happening, I have to shift gears and get into something else. Even if it's just a distraction. And the less space I have made in my life for those thoughts and the energy they bring with them, the more positive energy/people/things I have attracted.
It's taken me 16 years of therapy, recovery, psychiatry, self-discovery and spiritual work to get to this place. It's a gradual process. But it does get better. It just takes work.
Hang in there, all you who are struggling.