Less people have this aspect in life. Be the person you really want and tell others your true inner feelings and thoughts more assertively. Even though you may fear that others may not like whom you really are and reject you, which are good, being open separates those people who are "right" for closer relationships from those who are not. If you present yourself honestly and openly from the beginning, you will attract or repel people much faster.
An important lesson about concern is that when we focus on external outcomes that are beyond our immediate control, we give up control of our emotions and will begin to feel anxious and helpless. The same is true in meeting people, approaching people, talking to people, trying to help people, trying to entertain people, etc. Focus on your actions not their reactions. If you focus on their evaluation or approval of you, spending time with you, giving back to you, or any other reaction outside your control, you increase your anxiety and helplessness.
Everybody ought to focus on approaching people, being friendly, talking and listening to them, showing your openness and honesty, your assertiveness and your positive thoughts. You can control what you think and do. The result will be that you are setting attainable goals that you have control over; knowing that can give you peace.
In the long run, you may not want to invest much energy in a relationship if you do not receive enough of what you want. However, in the short run, focus on your actions as ends in themselves to "practice your act" and be the kind of person in a relationship that you want to be. Eventually others will respond positively as you get better at it and as you approach the right people. How many do you help without expecting anything in return? How does that affect people around you?