[Knack]

Often it's a vicious circle. You're shy, introverted with a lack of self esteem. So you start avoiding social interaction. Also if you're in an interaction you can't enjoy it. You often are afraid to act non-conformal. Avoidance leads to less self-esteem and social skills and so on.

You need to tackle the problem on all fronts.

1) This is about your learned behaviour. You have to relearn. As some mentioned before, do some training. Stuff like going out alone. There're programs for stuff like that. Do it professional! That's the most important thing right now in your life! Don't rely only on internet ressource, even if they can be a great inspiration. Go to a therapist if you think that your shyness (or social phobia) is a problem, e.g. if you can't go to salsa dancing because you're to shy. You must break the avoidance circle.

2) Work on your own thinking process. Often, people don't know their own needs or don't dare to stand up for them and try to compensate by being great to get attention. That's a dead-end street. If you don't understand how you "work", the training ( 1) ) can only be of shallow impact. It's really important to unveil your thougts and emotions. I like the Yoga approach very much. To me, it's sound and practical. swamij.com is the greatest resource on the planet. It's a lot and takes time to understand. You could start at the articles about Karma. The kind of awareness and unattachment you step by step achieve makes you stronger. Stronger to understand and handle your legitimate desires. (which does not mean, supress them. In your case, don't supress your loneliness but go out to socialise. But overcome your fear and go to the salsa dancing event.)