Don't give me the human nature crap, I've done it! You have to get outside your animal ego.
The way our minds are framed when we are born is to want to balance being with others vs being with self.
The more you are alone or stay away from people, you will go through a pain period (exactly like exercise) until your body acclimates. You have to also think and meditate and ask yourself: Why do I feel alone? You really have to want to analyze your own emotions and use the logical half of your brain to convince yourself that your emotions are just bullshitting you (because they are!) People put too much trust in what they think and feel, instead of just ignoring it until it passes, because you get that dominant view from society by osmosis just growing up.
One way not to feel alone is to think of everything about people that annoys you
Also to get passionate (really passionate) about learning or interests you can do by yourself, being alone is REALLY REALLY GOOD for the intellect, what might help you along is studying philosophy, you don't have to get deep, just go read quotes from plato or socrates, etc. There's tonnes of good stuff out there.