huajiro, I am interested in knowing--are you a pretty outgoing, extroverted person? The reason I ask is because I have siblings who are, and they seem to have the same problem with friendships. They have loads of friends, but very few of them are actually close friends--the majority of them are fairweather friends, who come and go as they please, and often take advantage of people.
I myself do not seem to have this problem, but then I am an introvert, who finds no need in having lots of friends. I am content with only a few close friendships, and all my close friends are wonderful people. I have never been treated wrongly by a friend, which I consider to be very fortunate. I guess because I do not make friends all that easily, I tend to be very selective in the types of friends I do make. When I say 'selective', I simply mean as far as their character and personalities are concerned. I just 'mesh' well with some people, and those that I don't 'mesh' with, I leave be, unconcerned whether they are my friends or not. My extroverted sister, however, seems to make friends with almost anybody, but always gets walked all over and treated badly too.
I'm just curious if one's temperment/personality has anything to do with the whole friendship issue....?