It doesn't mean that they don't have friends of friends who might be single and looking, or that someone might enter one of the networks tomorrow.
Just as someone who wishes for Lady Luck to smile on them must at least but a lottery ticket once in a blue moon, so must the one who desires a relationship (or anything else) take steps so if it's their lucky day and all the stars align for them, that it would be possible for the cosmic forces to actually deliver.
You seem quite fortunate in that despite the negativity which you portray here (both from your words and how you describe your interactions), that there are many people who are proactively reaching out to you.
As Gerald and others have suggested, you should do your best to befriend them. If nothing else, they'll help you better understand one of the core concepts of any relationship - the give and take.
In a good relationship, one should only be worried about giving, for if everyone gives and is generous in their giving, they need not worry about what they're receiving. And society is also better when we focus on trying to improve it and help wherever we can, rather than to vainly seek personal benefit. To quote President Kennedy "Ask not what your country can do for you – ask what you can do for your country."
And so, let me ask, what have you done for your community? And if the answer is nothing, that's okay, for tomorrow's a new day and a chance to change yourself and your community for the better. And sooner or later, that new and improved you will get noticed, though when we give and share, it should be for the sake of genuine giving and sharing and not for ulterior purposes, though secondary benefits may arise.