My two cheap words of wisdom:
Sometimes, without realizing we send subtle messages to the people around us that make them don't take interest on us.
It could be as simple as a lack of confidence on our posture or on our voice. And we can only change our atitudes if we change our mind frame. If you don't believe in yourself it becomes harder for people to trust you. Not because you are a bad person or not because you are not worth to know. It's just the image you present.

I don't know you in particular, so I am just speculating.