I'm actually alone
Why do you think you are all alone?
I feel excited, but no one is as excited as I am and I can't share it.
If you are often feeling alone, and you feel like you have to change that, you should try to talk to someone.  A professional can help you to understand yourself better, and to try to ease your way into social situations.
I think I'm in a good state of mind at the moment.
You can be in a good state of mind for now, but if you still feel like you are alone, you can seek help for that. I am sure that your friends and family will help out as well.