You may be experiencing isolophobia; the fear of solitude/being alone. I’m not sure what to recommend on how to help with it, though I’m certain there’s books that will offer support and guidance on how to cope. What you need to remember is, there are multiple reasons why someone may not answer your calls. They may be busy, and you need to remember it’s not something they have against you as a person. It brings to mind David Walliams, a British comedian who suffered from isolophobia. He did charity work and swam the British channel and described it as ‘redemption’ and a ‘relief from his depression’. Perhaps there is a hobby you could take up that would distract you, maybe even help you socialise? Alternatively there’s a number of social networking sites which could help you branch out and meet new people. Just remember, in the words of Michael Jackson, “you are not alone”!