I feel you on this. I have social anxiety disorder and so far it's like the single worst hand I could've ever been dealt in life. Everything that could've gone well for me has gone wrong because of SAD, and it seems to be an incurable and chronic condition.
If it makes you feel any better, intelligence means very little in life. A lot of my coworkers are broke and dropped out of school, and some of them lack just as much common sense as I do, but they still do pretty well in life and they seem happy. Lots of very stupid people get really far in life. Just look at all of the people who work in politics and sleazy sales and stuff like that. Being smart doesn't matter at all outside of like middle school. Even in college, you can't count on success if all you do is get good grades.
Try not to blame yourself too much. No one chooses to be born, and you don't have to make something of yourself in order to be happy. You'd be surprised how many people skate by and waste opportunities yet still feel very satisfied with their lives. People in good situations miss chances and so do people who are stuck between a rock and a hard place. I think that sort of thing is less about us as individuals and is more about a system that has failed us. It's not our fault that we can't see a way out of our circumstances yknow? With the proper resources we'd always have a chance to break free and start over, or at end it all peacefully, but society isn't like that yet unfortunately.