My friend you need professional help. We are not psychologists nor psychiatrists.
For starters the only way to meet friends is to be outgoing, being an introvert makes this very hard, but if you really want to make friends you are going to have to deal with your issues and talk to people. Believe it or not, it gets better with time and as you grow.
On the other part, grades don't mean a thing, and you really need to stop looking at things as if it was the professors fault. If you really feel that college was lacking in some way you need to either change college or make the best of your situation and study by yourself what you think your your classes are missing. In a way is as much your fault as the professors. That being said, the past is the past and there is no point dwelling on it.
The reality of your situation is very simple actually. You want to become more extroverted to make friends? Build something where you have to interact with people. You want to become better at 'python programming'? Buy a few books and build something in python, and when you're done reread the books and build something in python (this is a recursive sentence!). You feel like college is full of people that don't care about you learning? You're right, because the only person that cares about that is yourself, and unless you're Will Hunting you really need to take responsibility for your life.
Also, go see a psychologist, or a psychiatrist if the situation is worse and will require medication.